in my opinion it is mainly because there is a lot of controversy circling the wallet softwares that do alert users of new versions. so developers decide not to include such features in their software.

in any case, you are in a decentralized world using a decentralized currency with open source/free software. it is your own responsibility to follow their vulnerabilities, shortcomings,... and learn how to increase your own security as much as possible. nobody is going to take your hand and do it for you.