firstly fiat has many many bad things. bitcoin should not be trying to attain FIAT status. it should not add more silly features to make it FIAT-esq by bloating up the txbytes which end up reducing the transaction count/utility potential.
pandering features towards big business and services while ignoring the concept of individual control is not a aim developers should be striving for
secondly bitcoin should remain as the open other choice to fiat. EG an escape route away from fiat. as oppose to trying to make it into and to replace fiat
bitcoin wont become the "one world" currency. and if it did. it will be a worse situation than the fiat situation average joe is stuck in today
doing silly things like shout out Myspace systems cant handle the membership so how about try facebook is not going to make myspace any better. and the same goes for the guys saying bitcoin cant handle X so try a different network
bitcoin should get back to being the slim, lean transaction protocol that just sends funds from one address to another. allowing more transactions per second, meaning more people able to transact. and also implementing a proper fee mechanism where those that spent their funds with least confirms pay higher price as a way to only punish spammers and make the spammers the ones that find other networks a convenience.
in the real world people only spend with their visa card 1-2 times a day on average. so yea bitcoin does not need to push average joe over to other networks. it just needs to push a small NICHE of spammers off the network and into "convenience" services and networks. bitcoin does not need to punish every user with higher fee's during spam/high demand. as a fee mechanism will just make those regular spenders pay the price while not harming the occasional shopper with surprise new higher fee costs
as for the blockchain data itself. there are multiple ways to handle it without having to pressure people to give up their individual control. again pushing people into vaults/custodians is not the future bitcoin should aim for