That really depends on the household demands, I think. I'd be bored to tears if I were a stay-at-home; we're an absurdly low-maintenance couple with a small social circle and no pets except a mouse, but I know other people who live differently. Here's an example from my social circle:

Andrea's partner works in engineering full-time; they live in a two-bedroom apartment and are both 26. Andrea gets up every weekday morning and walks the dog, makes breakfast for everyone, and drives her partner to work. When she gets back, she does the breakfast dishes, makes the bed, and takes care of a task like laundry or grocery shopping. She generally takes a break midday to walk the dog again, go to the gym, and have lunch; she also checks on the neighbor's dog who's home alone all day.

In the afternoon, she might do some cleaning, pay bills, schedule doctor's appointments (and haircuts, family visits, vet appointments, therapy, vacations, dinners with her partner's coworkers, you name it) for either/both of them, plan meals, go get the car fixed, pick up medication, get holds from the library, or go to the vet. Then she does her own thing for a while, which is usually vlogging, painting, DIY home improvement/crafty stuff, cosplay, or working on tricks with the dog. Then she starts dinner and picks up her partner from work. After dinner's over, she makes lunch for the next day while her partner does dishes, and they end the day by walking the dog together. Two days a week she also volunteers for a youth reading program. Weekends are totally free except for Sunday night meal prep.

She's certainly not the busiest person I know, but she's got a reasonably full life.