Hi!
My point is that it is not a given that we should follow any WIkipedia for anything. Also the point of romanisation of Russian is not for the benefit of Russian speakers, it is for the speakers of English.
Same people may speak more than one language. And for English speakers, letters like š or č are not the most familiar either. Moreover, mismatch between Wikipedia and Wikidata would only confuse people - is Shchedrin and Ščedrin the same last name or different one? How does one look up for it? I think departing from commonly used way would just add confusion and not really help people, neither experienced nor new.