For non-technical holders of BTC (i.e. the mass of the BTC population), the risk of inanonymity and centralisation still there: as they have to entirely rely on their wallet providers? If such wallet providers are hacked or meddled with their users, the users won't have anyway to protect themselves or anyone to make a claim on? Their fund in BTC is entire at the mercy of the wallets?
How you think BTC would work for the ordinary people in the future to replace their current existing financial assets and management with fiat currencies?
Not all wallets are centralized... I do not think wallets are the weakest links if you choose a good one that gives you complete control of your private keys..
The weakest link is always the human. You can have the best hardware wallet if you don't know how to use it. You can have your private key hidden somewhere, you can write down your seed on a paper and laminate it, and hide it too, if you take a photo of your seed and store it on your phone (just in case if it's urgently needed...) then it's a big mistake also...
Every kind of wallet have it's own weakness and strength.
I use hardware wallets to store and web wallets to spend (and not vica-versa). You just need to know the level of the risk and act accordingly. Web wallets are also fine (despite of you don't have your private key) for a purpose of spending smaller amounts.