Lack of competition, poor customer service, high prices, regulatory capture, lobbying preventing cities and municipalities developing their own service, price fixing, ISPs that take lump sums and tax rebates from the government for "infrastructure development and expansion" that don't materialise, lack of net neutrality, ... ?
Are we talking about Technology or Politics? As far as technology goes, it's not actually far from a 'highly-developed' country, right? Gigabit in some places (and growing), really decent broadband in others. Free wifi is ubiquitous, cellular technology is also really decent in places like the frontier states - Eastern Oregon, Montana, etc. Not to mention lots of actual technical hardware and software development happens in the US like Loon[1] and Starlink[2]. On the software side stuff like HTTP/2[3], AMP(for better or worse)[4], Chrome, Firefox, etc. originated in the US, didn't it? I'd argue the US is the most 'highly-developed' country for Internet technology, but I'm biased since I am from the US.
If you're just complaining about politics, I won't argue.