Because it takes away development resources from actually useful things. And f.e. taking the examples of Signal and Keybase, both their crypto wallets/implement

Because it takes away development resources from actually useful things. And f.e. taking the examples of Signal and Keybase, both their crypto wallets/implementations are about the most useless possible. Keybase b/c I know no one who actually uses it as a messenger and it uses stellar/lumens, Signal b/c it is apparently impossible in most countries to actually get tokens to load / unload your wallet.