The problems are the (often abusive) preboarding of whole tribes with ONE child, people asking for a wheelchair for their convenience when boarding (and upon arrival then storm out of the plane walking) and the cheap *G enjoying the same treatment as SEN.
It will be funny to see how "group 1" will be handled at European outstations

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But there is worse when it comes to boarding: South America (especially Brazil) where the "elderly" over 60s are pre boarded and children are sacred. Must be kind of a law there.
P.S.: I am 63 (extremely fit), but always stand in the business / premium economy class line there

. And btw: never choose row 1, it makes for a more relaxing (handbaggage) experience.