I have a theory that about 97% of developers and managers completed the cookie consent (or whatever) on their own product 5 years ago and hence never see it again, and they have no idea how bad the experience for new customers actually is. So the developers and bosses all think they're doing a great job and they've got a carefully curated homepage, even though the regular users get a cloudflare captcha, then a cookie…
We use a third party cookie consent service. It shows different things depending on your location (and allows disabling different types of cookies depending on your local laws). Lawyers mandate it. It's easier than having to figure out the laws everywhere on our own. To me it shows a banner that stays out of the way. But I couldn't tell you for sure it doesn't cover the whole page to other people.
Cookie banners aren't a force of nature. They are required solely because you want to track people. Not tracking people? No need for a cookie banner!