I have never downloaded a special protection program for crypto like that on my computer, because in my opinion the most important thing to protect our own wallet is to keep our private key properly, and don't tell anyone about our private key, and avoid all phishing things site
The more third-party wallets, apps we download and install to use, the more risks we take ourselves. I totally agreed with you that keeping private keys safely is enough to protect our funds. Of course, computers need to have protections from threats and we should spend small funds to buy and install reliable internet security / antivirus softwares. I suppose to install internet security softwares, which gives more advanced protections.