You won't get the 1980s experience without busy signals, mom telling you to get off the phone with your computer, and sysops who demand upload/download ratios.
My father was an engineer and I guess saw the value in uninterrupted Internet. We had three phone lines in our home..maybe we should have just gone with ISDN now that I think about it.
ISDN was a huge PITA to get to a residence. It took months to get installed; I think there was one person in California who actually did the installations.
I later moved from one apartment to another in the complex; it would have taken Stan another 6 months to move the service from one address to another so I just opened up the phone panel (wasn't locked) and moved the wires -- there was a 1 week period where I was paying rent on both...
There was an 800 number in the panel "contact us if changing this so we can update the 911 database" I called it, explained what I did and that was that. Maybe; I kept getting billed, I kept the service, the billing info went to the right address; I never did call for emergency services to see if they'd show up.
ISDN was certainly nice, though. Ah, the 90s, what a time to be alive.
ISDN BRI service became fairly popular during the big dialup ISP boom of the mid-to-late 90s. I worked for a tiny ISP during said boom and we would somewhat routinely (again, we were quite small; the other big local ISPs ordered 100s to 1000s of ISDN lines a year) order ISDN Centrex service - as the unlimited ISDN service offering was then called from Pacbell - for our customers. Many many ISPs sold a crapload of Ascend P50 ISDN routers. We even sold a few to some of our business customers. It worked pretty well. Once we even drove down to the Ascend offices in Alameda to get our Ascend digital modem box RMA'd.
But yes ISDN was generally quite exotic for the consumer market. Centrex service (or whatever the particular RBOC chose to call it) even moreso. It was as close as most consumers could get to "broadband" in the 90s. I used it myself at a couple places including my small apartment in Sacramento. It didn't seem too hard to get it ordered and setup. It may have helped that we knew a Pacbell tech, the dad of one of the principals at the ISP I worked at. Not sure if he helped grease the wheels but he may have. He pulled 100 pairs into an apartment where we temporarily hosted the ISP. Pretty handy guy to know back in those days and for that particular business.
Later on I've only seen ISDN in PRI form. When I later got a "real job" in an IT department PRI was commonly used for the Shoretel gear we had. I never worked on the telecom side for bigger companies though and of course almost everything went to 100% VoIP eventually.
Yeah, I somehow ended up being responsible for the college campus modem bank a bit before I got my home ISDN setup; a pair of livingston portmasters and a pair of T1s that connected them to the phone co.
One of the hardest / most confusing problems I ever had was with that stuff -- TPC gave me 2 hunt groups (one for faculty/staff the other for students). One worked fine the other just wouldn't work at all. Eventually (after turning off the "broken" one and still getting a login/PPP prompt when dialing I called TPC and asked "hey -- your docs have these 2 hunt groups -- are you _sure_ they're right?" and they'd actually given me another org's phone number for one of them and that other org also had a livingston portmaster on it. Sigh.
SDLC phone network stuff is fascinating -- "why is it all on one clock?" (synchronous data link control) -- because when it was invented it was absurd to presume you could get enough ram to buffer things for packets (ha! What's a packet?) -- it all just happens at all at once everywhere.
Another time someone dropped a backhoe on the cable trunks between the campus phone bunker and the campus; I glanced over and saw the techs patiently stitching back together the eleventy billion cable pairs between the switch and each phone on campus. 30 tons of copper later got replaced by 500 pounds of memory...
In Belgium the phone company (wholly government owned) charged an arm and a leg for ISDN BRI, so I never got one installed.
We lived far from the exchange (5km), which at first was still a rotary when my BBS went up so it wasn't even an option. I can still remember weeping with joy when it got replaced with an Alcatel System 12 cause of my new transfer speeds and reliability.
Funny thing, the rotary switch was in a building next to my high school, you could see the vertical rotaries from the street next to the main entrance.
In 1989, I managed to persuade UIC to let me borrow a terminal and 1200bd(!) modem so I could connect to their IBM system from home. I remember how inconvenient it was to lug that terminal home by public transit. I ordered a dedicated phone line for it and it was a shame that I had 749-7491 as a number that nobody would ever call (and that I gave up when I returned to California in August).
One of my useless skills back then was being able to recognize modem speeds, brand and sometimes (especially Motorolas and USRs) model just from the handshake noises they made.
For a little while, I could recognize my old man's BBS' individual subscribers calling in just by turning up the volume of the modem on top the 386 box...
in the days of 7-digit dialing, dialing the Compuserve access number in Watertown MA (which one used from Cambridge MA) played "camptown ladies sing this song"
I was the Compuserve rep for Interplay back in the day, and the account number (76702,1342) will be forever burned in my memory. That account was free for some areas of CIS, but not all of it (much to the chagrin of one of producers, who ran up a $1,500 bill in one month of gaming).
Had my own line in the mid 80s. In the East Bay (SF Bay California) we had a multiline chat / gaming / etc. bbs known as Popnet. It was a base for a dozens of individuals meeting and socializing and still staying connected nearly 40 years later. This was in addition to the dozens of BBSs in the area - 925, 510, 415, etc.