The root problem for all these complaints is the pricing. There will always be players who are inconsiderate and want everything for free. But that's not really what's going on here.
I want to have fun, I think that's a pretty reasonable expectation to have for a game. I can spend $60 on a game like RDR2 and have fun. Or I can spend $200 on MT in Rivals and not have fun because that won't be enough to get my units to the level I can place in.
I'm good enough I stay around an 80% win rate, and that's when I'm going up against higher level units. But I have had plenty of matches I lost where I know it was because of just one level of difference in units. For example, a level 11 Rhino kills a level 10 missile squad, survives with no health visible, and takes a platform to launch a missile. At the higher ranks just one level can be critical.
If I'm not going to spend money on the insane deals, then how else an I going to get my units up so I can actually have fun playing against equally skilled players? One way is the ladder rewards. Getting them the first time was pretty nice. But now we've gone from 3x purple crates to 1x gold. That's several factors of difference and is hardly rewarding by the time you get to level 10 units.
I'm frustrated that the MT available are too expensive to even consider buying. On top of that, what they provide scales poorly with your level. I feel a lot of players share that frustration.