“Should you fix errors and contribute to Google Maps for free?”
I feel the same way about OSM. It may be mainly made by individuals in there spare time, but the big tech companies are making millions of it. The same as free and open source software (FOSS).
Apple uses OSM data in parts of the world where their commercial partners don’t provide data. They are reasonably good at fixing and contributing data to OSM in those regions. They employ nobody in the OSM community.
Microsoft Bing uses OSM in several regions, and is slowly moving from it’s traditional providers to OSM globally. They provide machine-learning (ML) datasets that they have computed from areal imagery. They employ nobody in the OSM community.
Facebook uses OSM world wide. They do a lot of quality-assurance (QA) work on OSM data as they were burned by a malicious user changing the name of New York City to Jewtroplis. As part of their work they now release a dataset called Daylight. Daylight is basically OSM data (+ other Open Data, like the Bing buildings) delayed with QA tests. They employ nobody in the OSM community.