F@*K Microsoft...

[Gman]

Not sure how you interpreted my comments to be a difference with Java Runtimes on different OS'es. This is a problem even on a single OS. Oracle ERP is certified for one Java version, a banking app on another, a web console on yet another, training video content wants another version of Java, etc. You just can't load the latest version of Java and have it backward compatible with a bunch of apps, particularly legacy apps.

I'm also not sure what you mean by Chrome being "Java based". The Chrome browser is part of the Chromium Projects. The Chrome browser and the WebKit browsing engine is written in C++. Chrome has dropped support for Java plugins. Maybe you're talking about JavaScript...which is an entirely different animal courtesy of Netscape?
https://java.com/en/download/faq/chrome.xml
Plugin-based content doesn't work on Chrome

In the past, many plugins were developed using an old system called NPAPI. Today fewer sites are using NPAPI plugins and they have often caused security risks on websites.

To make browsing with Chrome safer, faster, and more stable, we stopped allowing NPAPI plugins on September 1, 2015.

Plugins that use NPAPI, including Silverlight, Java, and Unity, won’t work.

As for older versions of OS X, Apple controls the hardware and software environment. If you have a Mac that is 3 years old or older, it may not be possible to upgrade the OS. That's part of the Apple model that encourages hardware upgrades if you want the latest and greatest OS and software.

Then again, my HP Elitebook 2530p from 2008 upgraded to Windows 10 just fine.

There are trade-offs no matter what option you choose.