All the reasons companies already don't successfully do that at the scale the RTO fear mongers claim they will: work culture, language barriers, various workplace and taxation laws that are/aren't in their favor, and frankly, experience and expertise. I bring value to a business that's worth paying American wages for, and so do so many folks I've worked with. This isn't to say there's not excellent engineers in other countries - there absolutely are. But (1) the tech industry has been centered on the US for so long that a lot of the top talent in this industry is concentrated here, and (2) the folks in other countries who bring the expertise and experience a senior or staff or beyond engineer in the US does aren't that much cheaper, because they know companies can and will pay high rates for the right talent.

Funny you mention Vancouver, which I used to live in and, talking to tech folks there, it was routinely called the "H1B holding pen" at the time - the place tech companies would hire folks and bring them to work at US wages while awaiting visa paperwork to head down to, say, Redmond or San Francisco. And BC famously has a huge brain drain to WA and CA on account of - you guessed it - salaries, and those folks often never went back to Canada. Back to: the talent concentrated here and demands a certain wage.

Surprise, companies have been outsourcing for decades and not slowing down, and WFH or not does not change any of that. My company's current headcounts are almost only in India, yet they are asking people to come in 3 days a week.

Right - and this resistance against RTO from a basis “companies are doing it just because of sunk costs” has a logical conclusion companies should increase outsourcing further.