Not true. Foreskin restoration uses a natural skin growth process called mitosis. Same thing that happens when people put on weight, or muscle, or get pregnant. Their skin doesn't get stretched thin and have less nerves relative to the area it covers. You do grow new nerves, and not just generic nerves, but nerves relative to the neighboring skin - so in the penis's case, the erotic kind.
I used to have just a little dot of sensitive frenulum, but after restoring a couple years it's around 1.5 CM long and this is a huge sensitivity boost for me. I don't want to oversell it, my penis was pretty great before, but I feel like I'm still not used to the improvement and will continue the annoying restoration process for these little gains gladly
When you're approaching the final moments before orgasm, relax your gooch/bridge/perineum. You'll feel your approach instantly slow, but if you achieve orgasm anyway, it'll be MUCH stronger and longer. It sort of slows the build up down, and results in a bigger O. Should only add around 30 seconds of delay - we're not trying to edge all day. Sometimes riding the edge feels great, so stay there as long as you can, but make sure you fall over, instead of losing the orgasm.
I used to wonder why my orgasms felt so different every time, but now they're always really good. You might have to dance a few perineum flexes in, to get over the hill, but try to avoid many. 100% practice while masturbating while laying down. It's super hard to have a fully relaxed perineum while thrusting. Also, try to make sure you're really hard before relaxing your P muscles. Softer orgasms always are weaker for me.
Advanced users may find there is a muscle you can flex in kinda in opposition to flexing your P muscles, but I'm finding it hard to explain... So start with the basics.