Since it's a software wallet, you can risk losing your BTC if the hacker gets access to your device. With a hardware wallet, they'd need to get physical access to the wallet and enter a PIN to steal all of your coins. Electrum allows you to create a cold storage wallet, but I'd certainly won't be using that to make day-to-day payments with BTC. That's why I prefer hardware wallets, even though some are expensive.
I believe you can also install Electrum on a live USB if you don't want to expose your wallet continuously to the internet. For example, buying a mini-PC dedicated to running a live USB with Electrum, or just an air-gapped device in general.
Some are using trezor and they say it is open source and cheaper than Ledger. In my opinion, I don't think anything is 100% secure, and Ledger is an example. We trusted them for years until they announced their damn service. The best way is that you divide your assets into parts and store them in different wallets, I think only then will our assets be more secure.
I don't think they expect Trezor or other open-source hardware wallets to be immune from exploits or bugs in the first place. However, it is certainly better compared to using Ledger after their latest fiasco. You can simply build your own device and verify the firmware/etc since it is open source. Using multiple wallets increases the burden of making backups. Sure you can do it, but if you use closed-source software then I don't see it as a significantly better option. CMIIW.