Collaide since when and why do people think this should be a part of the game
There is not a clear decision whether wallbugs should be banned or not to start with, considering it is not really an exploit just an unintended game mechanic in the same way c-taps, rampslides, jumpbugs, speedshots, edgebugs, and texturebugs are. I know the last time I asked an RGL admin they said wallbugs were allowed. I don't know etf2l's status on wallbugs, but randomly removing a skillful game mechanic that is allowed in competitive play doesn't make sense.
However, the most important reason wallbugs should be part of the game is how essential they are to jumping; some jump maps would become impossible without wallbugs and any world record using a wallbug could become unbeatable if it was used to save time. On some maps these wallbugs are unintended but others wallbugging is the intended strategy so it would ruin these maps and reduce the amount of skilled mechanics jumping can use.