My guess is that the laser mining respawn is unusable for SSDsThis is literally impossible, unless their code is an utter mess with all kind of hidden bugs lurking in the background, bugs they never actually bothered to fix, only masked away using lazy tweaks. Bugs you leave unfixed in your code before you implement a whole new feature on top of the project (something they have been doing notoriously for years now) will always surface sooner or later, in a very hard to track down form...
Normal (laser mineable) material content has absolutely no problem respawning the intended way (after some time, irrespectively of relogging and the distance from the rocks). They should have followed the exact same respawn mechanism with SSD's as well, simple as that.
Laser mining has individualised depletion - the game remembers which asteroids you've personally touched for 2 hours, but you can mine a rock someone else has mined, even if you can see them mine it.
Core mining has shared depletion - blow up a rock, it's blown up for everyone
Abrasion and SSD used to have instanced depletion - everyone in the same instance sees the same thing but there's no persistence - leading to relog exploits.
Changing abrasion to individualised would have the odd effect that if you were mining in pairs, you'd see the other person blast a chunk off, but you'd still see the deposit be there. If they tried to avoid that by changing it to shared instead (perhaps with a shorter respawn time than cores) then I think this would be a plausible result, even though they may have thought they were using reliably working code for it.
They could perhaps have left abrasion as it was, but we all know that just means an abrasion-related relog exploit showing up in 3.8
(Regardless, they should have tested it better pre-release to pick up on this sort of thing)