You mentioned a used model that is over 5 years old as an example of "a new computer", and "1k" as "not expensive for consumers". It is honestly impressive how well you undermined your own point.
> If enough consumers aren't able to use the website, then business wouldn't use it.
I sincerely doubt any business owner would approve of losing even 10% of their potential users/customers if they knew that was the trade-off for their web developer choosing to use this feature, but there are disconnects in communication about these kinds of things -- if the web developer even knows about compatibility issues themselves, which you would expect from any competent web developer, but there are a whole lot of incompetent web developers in the wild who won't even think about things like this.
Most web devs get screemed at (by their peer reviewers or [preferably] static analysis tools) if they use a feature which has less then like 98% support without gracefully denigrating it, and rightfully so.
But your GP is in a massive minority, if every developer would cater to 11 year old browsers we would be wasting a lot of developer time to inferior designs, with more hacks which brake the web for even more users.
I don't know about "most". For various reasons, I use a 2-year-old browser on a daily basis (alongside an up-to-date browser), and I routinely run into websites that are completely broken on the 2-year-old browser. Unrelated to outdatedness, I recently ran into a local government website that e-mailed me my password in plaintext upon account creation. I have no way of accurately quantifying whether "most" web developers fall into the competent or incompetent bucket, but regardless of which there are more of, there are a significant enough number of incompetent ones.
I think a very common browserlist target is "last 2 version, not dead, > 0.2%". So if you have a 2-year old browser you are probably dozens of versions behind and are very likely in that 2% of users which developers simply ignore.
Going back 2 versions, only ~50% of Chrome users are on v140 or newer. If you go back another 2 versions, that number increases to around ~66%. Going back another 2 versions only increases that to 68%, with no huge gains from each further 2 step jump. That you think your target gives you 98% coverage is concerning for the state of web developers, to say the least.
After checking further, almost 20% of Chrome users are on a 2+ year old version. If you handle that gracefully by polyfilling etc., fine. If you "simply ignore" and shut out 20% of users (or 50% of users per your own admission of support target), as I have encountered in the wild countless times, you are actively detrimental to your business and would probably be fired if the people in charge of your salary knew what you were doing, especially since these new browser features are very rarely mission-critical.
> If enough consumers aren't able to use the website, then business wouldn't use it.
I sincerely doubt any business owner would approve of losing even 10% of their potential users/customers if they knew that was the trade-off for their web developer choosing to use this feature, but there are disconnects in communication about these kinds of things -- if the web developer even knows about compatibility issues themselves, which you would expect from any competent web developer, but there are a whole lot of incompetent web developers in the wild who won't even think about things like this.