In particular, despite the risks, I would say that putting your Bitcoin in Coinbase is far safer than physically holding your own keys since the risks of that are far greater than storing your keys with Coinbase. Holding your own physical keys for significant amounts of your savings, in fact, is downright dangerous and I wouldn't suggest anybody do it, despite any systemic risks with Coinbase.
This is simply irresponsible. There’s no insurance if Coinbase goes bankrupt. Instead of taking responsibility for your own money-- Bitcoin's very purpose-- you’re trusting a broker that has every incentive to gamble with your funds.
The right approach is to learn how to properly set up an airgapped wallet and educate yourself on security. Relying on trust in others is unforgivable, when history is filled with breaches of that trust.