IMO Co-op vs AI shouldn't give exp after around level 15-20
Allowing bot matches to give exp past level 15-20 brings in a whole boat load of people who enter ranked matches without much experience in jungling or higher level plays.
IMO this is mainly targeting people who play mostly bot matches till level 30 and then trying out ranked.
Top and mid laners who wait forever for their jungle to snowball their lane in bot matches will suddenly have no idea how to respond of defend against ganks.
Bot players who don't ward suddenly are confused on how they are losing lanes so hard.
League should have players prepared for ranked instead of letting them walk into a vicious world of players who try too hard.
If Bots can't jungle I really don't see any reason why bot matches should give any amount of exp past level 15-20.
At the very least, practicing dominion makes you a better skirmisher and stay aware of the map and control points.
With bots, sure you can practice farming, but the bots often don't try to aggressively zone you or prevent you from wailing on them with your jungler or even utilize wards for that mater. On top of that, farming only gets you so far in a game.
In bot mode, you can just find an extremely good duelist and just farm on bots by taking advantage of the holes of their inteligence instead of learning to farm.