This isn't generally true at all. The "all tech companies are going to 996" meme comes up a lot here but all of the links and anecdotes go back to the same few sources.
It is very true that the tech job market is competitive again after the post-COVID period where virtually nobody was getting fired and jobs were easy to find.
I do not think it's true that the median or even 90th percentile tech job is becoming so overbearing that personal time is disappearing. If you're at a job where they're trying to normalize overwork as something everyone is doing, they're just lying to you to extract more work.
It starts with people who feel they’ve got more to lose (like those supporting a family) working extra to avoid looking like a low performer, whether that fear is reasonable or not. People aren’t perfectly rational, and job-loss anxiety makes them push harder than they otherwise would. Especially now, when "pushing harder" might just mean sending chat messages to claude during your personal time.
Totally anecdotal (strike 1), and I'm at a FAANG which is definitely not the median tech job (strike 2), but it’s become pretty normal for me to come back Monday to a pile of messages sent by peers over the weekend. A couple years ago even that was extremely unusual; even if people were working on the weekend they at least kept up a facade that they weren't.