If by the tech industry you're including startups, then those all firms with money due to future expectations of success, not actual success.
Then you've got firms like Apple, Google and Microsoft with so much financial momentum they could lose half their employees tomorrow and their quarterly results would go massively up.
The cases where WFH matters are all the firms in the middle. Non tech firms, for example. Firms that are mature, but which don't mint money hand over fist.
I've worked from home for years and it works fine for me, but I also have a friend who's a senior tech exec at a non-tech firm. Sometimes he invites me round for BBQs on a workday, where he is "working" but no actual work gets done. Sometimes he naps in the afternoon. My brother is a tech executive at a software firm, his work consists of a few meetings a day and the rest of the time he chills, takes care of his kid or works on side projects.
For the employee? It's great. For the employer? Yes, you can view it purely transactionally, as in "we pay you for results" but in reality contracts aren't worded that way because it's impossible to write down in an understandable and conflict-free manner. So people are always being paid for time spent, and they then don't implement their side of the contract whilst expecting the firm to do theirs. It's tough, I don't know what the answer is, but to not see the employer's side of the story isn't right.