That's generally not true for workers in the US. If you are self-employed, yes, you can take a home office deduction, but not if you are a W2 employee.
The US used to have an "unreimbursed employee expense" itemized deduction, but even then there was a pretty high floor (had to be more than a couple percent of your total income) so most people couldn't make use of it. That deduction was eliminated in the 2018 tax law.
The "massive tax benefit" is not that large for most people. Perhaps if you have dedicated office space and a large mortgage.
I did the math for my T2200 and the total tax benefit was $500/yr.
You don't have to do that in Canada.
“You may have to report a capital gain if you change your principal residence to a rental or business property, or vice versa.”
https://www.canada.ca/en/revenue-agency/services/tax/individ...
However, it looks like there were some changes that may allow you to avoid it (business use was a small fraction and you didn’t take advantage of tax benefits from business use).
But most people don't know that there are massive tax benefits to working from home (at least in Canada) you can write off the percentage of your house you work in of your rent and stuff like that. That alone can equal a $1000 a year or so.
But from a company point of view, getting rid of the office is a massive save in money, so I suspect some will increase salaries or offer other perks such as skipthedishes accounts or what not. Most will just pocket it though.