An Apple update this afternoon (15 Feb. 2023) restored almost all my favorites icons in Safari 16.3. My version is now: 16.3 (16614.4.6.11.6, 16614). I'm still using a 27" 5k iMac from late 2014. I don't know how many of us are left but I am grateful to have had 9 years of that gorgeous display.
Off-topic, But I am amused to see Mac users switching to Chrome because Safari seems slow. Perhaps that's the price for Apple's web security. Both browsers have the same Web-kit kernel, but the Chrome app file size is much larger than Safari's. That is, of course, because it takes a lot of code to track and catalog a user's every web experience.