Prices stay high because ISPs are able to block competition with stupid compliance laws (e.g. obstacles to run cable, obstacles to register, and lawsuits galore). In my area, prices are pretty reasonable, because we actually have decent competition. We have:
DSL
Cable
local ISP - based on failed old muni fiber rollout (stupid state laws)
radios - works well for some people
5G-based services
upcoming muni fiber project
The muni fiber project is doing a lot of work here, but our local ISP is pretty decent as well, with speeds from 20/10 to 1000/500, from $40 to $125, taxes included in price (5 tiers total; only had two crappy tiers before muni fiber project announced). Cable prices are also reasonable because they need to compete with the local muni ISP, but they hide fees and whatnot, so I don't bother with them.