Another thing that worries me is points. Everything went up for the new edition, but the non-secret was that marines were dramatically undercosted to start with, so if 15% was the average hike across the game, marines needed to be around 20% to make the change an actual nerf. And that was offset by the changes to blast weapons and vehicles.
But now we're seeing (potential) large buffs in their arsenal; multi meltas/meltas, heavy stubbers, onslaught cannons, accelerator cannons, safer plasma, more well rounded storm shields. And those points increases feel even less relevant.
Depends a bit on if these changes apply to equivalent weapons in other factions. Some of the potential buffs, 2 DMG heavy bolters, better autocannons, deadlier multimeltas work best against popular marine units (intercessors and all of our high wound no invulnerable save vehicles).
I agree though if marines got an increase but their weapons get proportionately better it’s not a nerf. I do believe marines got a higher points hike on average than most armies with some targeted (and necessary needs, but I could be mistaken. Custodes and a lot of other elites went up less, horde infantry higher proportionately was my general observation. Marine outliers like the relic contemptors will probably see some changes as well.