I see many sites still running v7 and I know v7 still has a massive amount of 3rd party module support. But v8 has been out a long time now and many of the extra modules v7 required were included in v8 core. I was lucky to do my website from scratch on v8 so never had to migrate a v7 site.
But key is this comment about v8.9 release: "This version is going to be the last minor version of Drupal 8 where you will find new features or deprecations. The next version, Drupal 8.9, will not include any new additions but will be very similar to Drupal 9.0".
See How Drupal 8 aims to be future-proof
Thomas Edison famously said, "The three great essentials to achieve anything worthwhile are, first, hard work; second, stick-to-itiveness; third, common sense." This quote made me wonder if "sticking-to-it" is contradictory to innovation; does it make you resistant to change? But, the more I pondered on it, I realized that innovation is fueled by perseverance.