If they took out the RNG and instead made it "collect X number of tokens," people would complain that the X number of tokens is too large or too small. Take a look at hunts to see what I mean.
At least with RNG, you can get it in as few as 1 run.
There will always be some facet of acquiring things in the game that doesn't work for you, because SE seems to want to try ALL of them.
Token drops? Hunts, GC seals, shiva, and the soldiery/poetics system
Random drops? Everything else
Also, as mentioned, random drops have been part of RPGs since RPGs became a thing. If it really bothers you THAT much, maybe the genre isn't for you.