One of the main things that I aspire to in this hobby, besides loving the music, is to attempt to reproduce it as it was recorded. IMO, that's the best we can do regardless of the format, or the care or knowledge of the engineers. It is what it is. So, if you love the music and it's only in mono, what's our job? Sure, you can stay away from mono recordings, but you may be missing out.
As mentioned above, much music is only recorded in mono, and a couple of years ago I wound up with my accountant's vinyl collection, mostly mono. I'm getting close to finishing off my final system except for tweaking, because I'm getting up there in age and it's time to unwind.
My plans are to cap off my system by adding a second arm with a mono cartridge. When I upgrade my phono stage, I'll also be adding a true mono circuit. I'm doing this, because it's important to me.
Kenny