I (and most of the people I know), have had the opposite experience as you. Essentially everyone I know has moved into corp landlord situations because the downside risk is a lot lower and there is a paper trail if you need to dispute anything. I have like a 50% hit rate on mom and pop landlords being awful, I can give three examples off the top of my head:

1. New landlords bought a place I was living in and wanted to do in their words "minor upgrades to the house", but during the construction they would "keep it livable" and not require me to move. I came back after work one day to my water being off (and a toilet removed), and they didn't turn it on for two weeks after that (and kept the toilet removed). I had to get a lawyer involved for rent reimbursement.

2. My water heater broke and flooded my house in the middle of the night. The landlord took 1 month to start fixing the completely flooded apartment, and then the landlord tried for a year (threatened legal action as a bluff) to get me to pay for the new water heater despite it being their property, and maintenance being in the lease as their problem. I obv never paid because it was basically just a shakedown.

3. My landlord tried to just not pay me a month of rent owed after they sold the property with me living in it. He called me several times trying to "make a deal", and I told him that it was a cost associated with him selling the house and that I would not leave until he paid me the month owed. He waited until literally the last possible day to pay me and yelled at me on the phone that I was being unfair despite it just being money he owed me.

Every corp landlord I have had has been by the book. Yes my rent has gone up marginally, but at least there is a paper trail and they do not try to do any of the crazy stuff I just described.

That being said, I did have one mom/pop landlord who built me a deck with a bike locker over the course of a summer once, that guy was great.