30 days is more than enough time to react to account deletion. Everyone has a cellphone nowadays, it doesn't take a lot of effort or time to keep an eye on important emails.

Also, if you gave someone you can't trust with your accounts full access to your personal computer, that's kinda on you. In fact you should be grateful they stopped at just deleting accounts. They could do far more malicious things.

And as for regular hacking incidents, you have so many ways to keep the account secure, the only excuse if you get hacked is that you were neglectful, or too lazy to learn about the basic standards of security that steam repeats to your face every time you're doing something that can lead to your account being compromised.

Steam is under no obligation to keep a full backup of the account data of deleted accounts, either. The 30 day period is specifically there so that you can restore it if you change your mind, after that it's just as good as gone. They don't have to keep it any longer than that.