I use 2020 model with 77% battery health. I get 4-5 hours screen time with less demanding task. I was power user before then I realise My screen time is more than 6 hours a day. I cut that down to 3-4 avg. SE did everything I want. Messaging, surfing etc. I will replace the battery in 2-3 months and will use the till it get the major software update. I guess still 2-3 years it will release major ios updates.