I am not familiar with the case, so I can't comment on that incident itself. The newest Electrum version is 4.3.3., released just a week ago. I have just gone through the release notes, and there is no mention of any serious vulnerabilities that were fixed from the version before. In my experience, 99% of all cases where people loss funds or have them hacked/stolen is because the user made a mistake. Fake wallets, phishing, malware, keyloggers, etc. Even the people he talked with from the signature campaign he managed are potential suspects who could in theory have given him an infected file.

If there was something seriously wrong with Electrum 4.3.2, I think we would hear many more complains than only that of julerz12.