People use the term casual out of context too much especially when it comes to completion of content. There is no "Casual Way" to DPS your way through content that require strict minimums. You either do the numbers or you don't. Rationally most of the player base will not hold you anything more than the required minimum to clear the content. When people say "I want to Casually clear content" that means take your time with mechanics not perform sub-par with skills and still expect to be rewarded.

If you come into content over-geared with Echo and you are STILL barely putting out more DPS than a Tank there is nothing casual about that. That is PURE lack of skill or regard for other players who took the time to at least perform optimally.

You will get bad attitudes but I doubt it will reach the breaking point. I think they would actually make people more aware of how they play and force the Player base to get BETTER not more elite.