The common justification offered by those espousing such views is that if the Trek they like fails, it will be replaced by Real Trek, since that is What the Fans Want. Alternatively, it stops such instalments from Tarnishing the Star Trek Name.
The perceived change of direction for Discovery in s2 has emboldened advocates of the former view, asserting that their reaction is responsible.
I've not been able to understand either view - failure does not invite further investment, and Trek has survived far worse instalments in Trek than the recent ones.