The pointlessness of MultiSig hot wallets

I gave it a thought for a bit it's quite laying on a surface. What's the purpose of MultiSig wallets if you don't have something that signs transactions offline? (e.g. cold wallet or a phone disconnected from the internet in Airplane mode with no SIM and disabled Wi-Fi driver)

For instance, imagine we have a 3-5 MultiSig wallet for redundancy (the tolerance of up to 2 compromisable seeds). So to make transactions, you have to store them on some device that is connected to the internet. Now suppose one of your hot devices gets compromised and you decided to store your other seeds on e.g. laptop and PC and let's just assume the best case scenario – they're both offline. So now hacker already has the access to your phone. Then to make transactions you have to either:

1) Approve transaction from every device in order, which makes it hella inconvenient

2) Store all seeds on one portable device

Now you see the problem? In overwhelmingly large amounts of cases if you download a malware it's your problem and your device probably gets hacked in a local network, not internally (something like wannacry.exe, but not that explicit, and to remind you, this virus is almost 9 years old already), and now tell me, what's the probability all of those "secure" devices will use one single router? Probably >99.99%

And them's the fact, buy cold wallets kids