Absolutely not true. I don't use Google Maps in Czech Republic at all as there is a solid local map provider[1] - (they offer whole world through OSM, so I use that on phone as well[2], but it's not that great). They lost some edge with Google going full-textured 3D few years back (actually the Czech map had it sooner, just not as useful). But other than that much cleaner rendering, equally good aerial or street view, better routing, POIs, richer layers ...
(edit: and two huge UX advantages over GM: no stupid random rotation - North is UP, and a very quick and precise zoom by holding control)
Anyway, I wouldn't be surprised if there were similar stories in other countries.
2. https://play.google.com/store/apps/details?id=cz.seznam.mapy or recently released as https://play.google.com/store/apps/details?id=cz.seznam.wind... (haven't tried it)