Yeah, we only have the one issuer, so it's not a concern. For pretty much every KeyCloak project I've done, we have also favored doing separate deployments for separate issuers, so I'd say it's not much of an issue, in most cases.
Regarding the optional standards, no. We've not run into an clients that would require or in many cases even support anything but the most basic OpenID Connect. I'm sure there's a point to supporting them, but I've never seen it being needed for your average use case.
Yeah, we only have the one issuer, so it's not a concern. For pretty much every KeyCloak project I've done, we have also favored doing separate deployments for separate issuers, so I'd say it's not much of an issue, in most cases.
Regarding the optional standards, no. We've not run into an clients that would require or in many cases even support anything but the most basic OpenID Connect. I'm sure there's a point to supporting them, but I've never seen it being needed for your average use case.