From what I've experienced here in cryptocurrency for several years, I haven't faced any issues using Electrum since 2018 until now. Since you're like op I can't focus on spending money to buy a hardware wallet.
Electrum is a very good wallet and highly recommended, but it is a hot wallet, and even if the wallet is open source and we are very sure of the code, what about you and your device, is your device free from malwares, do you watch porn on your device, do you click links without giving it a second thought, Electrum is a good software wallet, but if used in an online device, the funds in the wallet are not safe, except it is just a small amount for your daily spending. But for long term and with huge funds, use electrum on one device as a cold storage, generate the seed offline and make sure that device is never connected to the internet, with Wifi disabled and airplane mode turned on, that's where you would sign transactions, then on a second device which is the online one, you use electrum on it for watching only and broadcasting transactions to the network, that is the safest way to use a software wallet if you can't afford a hardware wallet.
Although, I also believe that it is good to use the hardware wallet as others say here that it is really recommendable. And as for the software wallet, electrum is also recommended here in my opinion and experience here as long as you update it if it says something that should be updated.
Updating your wallet sofware regularly is good, but that is not only where the vulnerabilities exists, as long as the device that holds your funds is connected to the internet, there are malwares, keyloggers and other forms of attack vectors waiting to steal your funds.