Leaving aside everything about centralized stuff, not your keys not your coins that everyone else ha touched.

The space argument is probably one of the worst that is, I can bet that you have on your phone more useless apps or games than all the wallets on google play would occupy, actually let me check since I have electrum on my phone with 4 wallets, good for keeping some dust.
80M! a huge 80 Megabytes of space, 80M of space in the age when you can buy a 128GB phone for 150 euros! Not even talking about expanding your memory with an sd card!
One of the worst arguments I've read so far to promote web wallets.