Not all X features are going to be implemented in wayland, right? If a feature has security implication, chance that it won't be implemented in wayland. It took them years to get screen sharing working, and that with a significant proportion of wayland users begging for it on every release. Chance that other insecure but useful X features won't be implemented in wayland unless they can be implemented with security in mind AND the features somehow got prioritized for development (or some l33t programmers suddenly show up with a patch and got accepted).
Many “insecure” features are implemented on a per compositor-family basis in the meanwhile. Like every wlroots-based one has this protocol, things like that.
Depends on your use case, I've been using it for years now and am yet to run in to missing features. There are a few features x11 is missing like different dpi scales between monitors which Wayland does. Sandboxing with flatpak is another big one as well.
I'm a big Barrier user, which has no Wayland equivalent. I also frequently make use of X tunelling over SSH, which had no Wayland equivalent the last time I checked, although it has been a year or so since the last time I looked into it.
