My impression was that it was even worse than AW/Blops3's implementation.
I didn't actually buy it, but that was my recollection from watching some Drift0r vids.
It was a very muddled system at launch (when I played the game) as it had salvage and the lootboxes, with variants available only via drops.
Now they have (from what I have seen on CoD YT videos) gone some way to fix this by giving season pass holders free weapons and the ability for those without a season pass the ability to earn weapons from completing challenges. You can then craft these variants with salvage (this salvage though still takes ages to earn AFAIK so there is still a massive grind here).
It is a huge step up from BO3, which was pure garbage.
It's a shame we have to go through this system of them ironing out their gouging systems with each interation of the game and they can't just get a decent system in place as Overwatch seems to do it right, and people love cosmetic stuff.