Over time this will all be abstracted away and typical users won't have to worry how it's all working underneath (unless they really want to).
Someone else can do that and then sell you the L2 token directly.
It's also quite easy to integrate with webapps.
We're still very much in the early days of this though, having to move between chains manually. There are bridges that allow executing contracts on other networks, and eventually apps will abstract the different layers away from users using technology like this.
Given that being the case, the general decentralization argument would be pointless. For the many users who need to be able to pay for their groceries quickly, you might as well use Solana then, since everyone needs to eat.
The whole point of Uniswap is to move away from these centralized exchanges. Perhaps using that has gotten more complicated to use or the swaps have also gotten too expensive even if it is on an L2; making that useless as well?