Our 4 year old (now 5) was depressed and anxious for months during lockdowns. Why wouldn't she be? People aren't meant to be cooped up together all day like that, and she needed space from us as much as we did from her. Space we couldn't really give her in our tiny home.
By the time she went back to school she'd been home, away from almost all other kids except her baby sister, for like 8 months. That's basically forever in 4-year-old time.
As to screentime, you don't know anything about those other "parents". If I let my daughter play educational games for 20 minutes so my wife and I can actually have a conversation over dinner, what's the problem with that?