Companies now block older browser versions
Now? This has been happening since the dawn of the web. At least the screenshot you pasted represents all of the big three rendering engines - it used to be common to see "Internet Explorer version XYZ required", sometimes with javascript to prevent you from using the site with any other browser (even if in some cases it would actually work fine if you simply spoofed your user agent string).
I have used kinda retro devices to surf the web at times
Most websites became HTTPS-only sometime after the snowden disclosures in 2013.
Over time old versions of TLS have been deprecated and eventually support for them is dropped from browsers and web servers alike. So, a browser from even 15 years ago literally cannot connect to most webservers today.
Planned obsolescence is terrible but it's a minor factor here: it's actually dangerous to use even (especially?) a slightly-out-of-date web browser because every new release fixes vulnerabilities which can be exploited to run malicious code on your computer. The planned obsolescence which prevents people from being able to have an up-to-date browser comes mostly from proprietary operating system vendors; to have up-to-date software while continuing to use somewhat older computers you need to use free/libre software.