Your 1&2 disadvantage for bitcoin no be anything for long term investors because bitcoin price dey increase overtime and 1btc=1btc.
Some people fit go dey careless with their seed phrase or click on malicious links with malware wey go make them lose their coins. Self custody easy if you follow the simple ways to secure your funds. Greed again dey make many people go connect their wallet for random sites wey go drain their funds.