Elite Dangerous - Combat Logging
Solution 1:
Yes, it is still possible.
It's considered cheating and a pattern of it can get you shadowbanned, especially if your opponents report it.
The peer to peer nature of the game means it is very unlikely that they will ever be able to prevent combat logging. There have been discussions of methods of automatically punishing combat logging, but none of those would apply to a single time doing it (since it's entirely possible to crash or lose your internet mid-combat).