Hard to say, but you definitely need to be doing a lot more than you are now before i’d look at that metric. One big week, and it all goes red.
I personally thing your FTP is just set too high. All the older workouts were much easier than what you’ve been doing recently. I’d just drop ftp a few % until these workouts are manageable. Vo2 and over unders are also quite mental rather than physical.
Don’t over think it, if you’re failing workouts, adjust FTP see if that helps and move on.