MetropleX It is my impression that this has bubbled to the surface because so many of us were / are Signal users, that are experimenting with different SMS messaging apps now that Signal has announced it will be dropping support for SMS soon.
Although I would obviously prefer to message 100% encrypted, at least in the USA, unencrypted SMS is used by a large percentage of organizations for 2FA, as ridiculous as this is in light of the lack of encryption. I recently shifted my default SMS app to the stock GOS messaging app, but still use Signal for my communication where the other party is a Signal user.
Since I work third shift, a significant amount of my waking hours occur when a white background is somewhat harsh on the eyes, thus my desire to see GOS Messaging allow for dark mode.
An incidentally, based on another post not too long ago, I recently became a monthly donor to GOS. While the few dollars I can give on a monthly basis are not going to help much by itself, I second your appeal for everyone here to step up and donate what they can. This is an awesome OS, and we all need to do what we can to support it.