we visited last year with my parents in their 70's both with walking difficulties. Its about a 2 min walk to the promanade with a slight incline-here there are bars and shops. I dont think there was a lift but the hotel kindly placed my parents in a ground floor apartment, away from the pool (which can be quite busy and noisy in summer) so they were more than happy with that. It is about a 10 min walk to the town centre along the prom (all flat) my parents would stop at cafes and rest on benches along the way.
There are a couple of bars right outside I would recommend Pepes for a huge breakfast.
The only downside is the pool is too small for the number of guests in high season and it was a bit of a free for all. Thankfully our apt was away from the pool above my parents.
If you can cope with that I would recommend the hotel.
Any questions dont hesitate to aks

Walking ? There's nothing that even resembles a hill in Puerto Pollensa.

Thanks very much for the info - much appreciated.