FWIW, I’m almost the same FTP as you. Mid 230s and topped out at 238 couple times, back to 231 this last FTP test after the off season and starting up the new plan for 2021.
Also, I’m 44 and my weight is just a hair under you and I have 40 hours a week job and a bunch of kids and all that too.
So I’ve had some of the same feelings and frustration you have. But there is one bright spot I can share. I posted last year the thread:
https://www.trainerroad.com/forum/t/ssb-ii-is-killing-me/
Well here I am a year later and ssbII is on the plan builder again. This time it isn’t killing me. I was about FTP 220 when I did this plan over a year ago. So even though only 10-11W higher now and it seems from my history that’s within the margin of fluctuation up/down, I’m now doing those same workouts without dying. Instead of limping through them and turning the intensity down a percentage or two, I’m keeping it right at 100. My HR gets up there and I sweat, but I just keep powering through and my legs aren’t failing and I feel great when I get it done.
So I’m sort of excited for the new AT program that can measure and show progress on more than just FTP because I feel like FTP isn’t telling the whole story. My FTP isn’t a lot different but my results during workouts are certainly different.