You shouldn't forget that blockchain.com has a exchange with fiat transactions available too.
https://exchange.blockchain.comIf you are using this exchange you have the same risks to lose your funds by leaving them on the exchange than stacking/lending them within this service. There are more decentralized offers with higher APRs (Azuro liquidity pool is offering almost 20% for USDT stacking) but I don't think the blockchain.com one is a bad one to avoid.
I did not forget 🫡 my point was, their custodial arm was established at a much later time [than 2011] so op's they've been here since 2011 has a catch in this case.
I do think they're a bad one to avoid though whether you wanna use it as an exchange, wallet or for gaining interest.
1. For wallets or exchange, there are better options out there for most use cases.
2. For gaining interest, op just has to look at all the custodial services who got hacked, exit scammed, had poor funds management or whatever reason they come up with. If there's something to learn, it's that we shouldn't let our coins sit on their custodial wallets for long periods hence this earn thing is a no-go.
A much better alternative is to hold bitcoin in a wallet that op control's and preferably in a non-hot wallet too.