I have the Robot and the Niche Zero, and it really is a great setup for the reasons you've laid out. Another reason to consider is that with a manual machine, you never have to descale it. The basket is easy to clean every time you make espresso, and the rest of the unit can be wiped with a cloth.

As for the physical effort, I think most people who don't have disabilities or chronic injuries should be able to handle it. I'm 5'3" and 120 pounds with no upper body strength, and I have no issues applying enough pressure. I fortunately have not had a shoulder or back injury since I got the Robot, but I think a step stool could compensate in that case for me.

My typical drink is a short americano, so I don't bother with milk. Sometimes for guests I microwave some oat milk, and that's usually good enough for anyone who isn't a latte nerd. If you decide you want a way to steam milk later, there are ways to do that without having a semiautomatic machine.