BF1 had it right. The basic weapons were decent and all you unlocked was variety and flexibility not raw power.
To be fair to DICE even BF4 (and BF3? I can barely remember) did it this way.
I've never understood the 'design'. It creates a fake power gap (that people call a 'skill' gap when it isn't) handing more raw power to people that have more time to play is a double-whammy to noobs and casuals.
Unfair, frustrating and off-putting.
And I'm someone who is now rank 128 and has a ton of time to play and a ton of unlocks. It's not fair and I don't want it. Something else I've never understood is supposedly 'skilled' players who are happy to noob stomp.
It's not going to change, though. EA/DICE want to push people to pay to unlock stuff.