I know of the solutions. I use a few of them.

I have multiple Playwright webkits on both Windows and Linux. I have Epiphany on Linux (not 100% same webkit). I have subscriptions for testing on real hardware.

This is why it seems to me that Apple does not really care about web developers.

No way, is Orion Browser available on other platforms as well now? Does it mean I can finally do tests for Safari (webkit) without owning an Apple product or paying for a vm? Incredible.