Not true.
MacOS releases a new version each year, the current MacOS landscape looks like:
- MacOS Sequoia (previous version, everything works as expected)
- MacOS Tahoe (current version, broken experience, basically Apple's "Windows Vista/8 moment")
- MacOS Golden Gate (next version, fixes what was broken in Tahoe, comes out in a month)
I'm on MacOS Sequoia because I have things that can't be broken by updating to Tahoe.
I also cannot test how my websites/webapps will work in a month, because Safari's beta (called Safari Technology Preview) only works on Tahoe and Golden Gate.
I cannot wait a month to update to Golden Gate because Golden Gate drops support for my iMac.
And I can't test the new version of Safari on my Windows or Linux devices because Safari isn't available for them.
I can test the Webkit browser, but that doesn't include the Safari specific changes that apple makes which I need to be able to test.
---
So, I can't test Safari until I wait a month and purchase a new apple machine.
(Oh by the way, apple keeps cancelling orders for new machines)