While I agree with your general gist and definitely your final paragraph,
> There are plenty of people with old android phones with no free disk space using ancient browsers.
How many people have 10 year old phones? I've got an 8 year old iPhone XR which I keep around as a backup/travel device because it's not worth selling, and the battery is… not happy even in airplane mode.
For me to have a 10 year old mobile browser, I'd have to have kept the iPhone SE 1 (or was it a 5c?) that I bought second hand in 2018, and not upgraded it since I bought it. I got rid of it because the battery wouldn't hold a charge for 10 minutes.