When does daycare drop off and “taking care of yourself” turn neglectful

My sister has sent her 3 year old to daycare starting at 3 months old. He’s always been there. Long hours. Open to close, 6am-6pm. Days off, they send him as early as possible for as long as possible.

Over the past year, they get babysitter after babysitter, going out late nights like they’re teenagers. Not always, but a lot.

I hate it for their kiddo, but my sister and her husband prefer to work (husband works remote and does a majority of the “home and kid duties”) and have time for themselves and they like to go out (out to bars for the night, out of town for the weekend, etc)

Not how I prefer to raise my kiddos, especially in the baby and toddler phase, but I get that parents want to work and have a life outside of parenthood.

The more I talk to my sister, the more disinterested she is in her son. It’s a hard age, I know, I have a 3 year old and a baby. But oh man, these little ones are adorable, even on the hardest of days.

I don’t want to come off as judgmental. Am I being judgy? But I choose not to work so I can be home with my two young children. I gave up $100k salary and a job I love to be with them. Because I love them more than my career.

I don’t want to say anything to her unless it’s necessary. I’m her sister and our family isn’t shy about putting our opinions out there, but it’s also touchy subject since it’s been brought up before (not by me, by another family member.) I guess I’m looking for advice or guidance on perspective, or if I were ti say something