Although I don't see widespread adoption yet if Matrix bridges aren't implemented by the common household names. Conservative organisations use solutions from Apple or Microsoft. There is no deeper thought behind it.
That said, I think they just did it because of trademark issues. Private users are probably converted by their environment and probably don't think too much about the name.
The French government's installation has been in the public domain for sometime (https://matrix.org/blog/2018/04/26/matrix-and-riot-confirmed...)
More recently the German Education authority has announced that it will roll out a 500K user installation - this is the world’s largest-ever single contract for a collaborative software service (https://sifted.eu/articles/element-germany-deal/)