I think this is by far the easiest solution and we have done a lot of that since the species complex option was added in 2019, but it’s still hindered by the fact that species groups aren’t an option yet. This creates issues where we’re using the “complex” option in places where it technically shouldn’t be which creates extra tension with people wanting to stick to the proper technical terms, and it also restricts flexibility since you can’t create a complex within another complex (I think we’re supposed to use “series” for that – again, technically incorrect and causes confusion).
I created or tried to help on flags on a lot of the large plant genera to get the ball rolling on introducing infrageneric taxonomy, but it’s a very slow process because it’s tedious to implement and before you can even do that you have to settle on what taxonomy system to use for the genus. Sometimes there isn’t a clear global taxonomy, other times there are competing ones. E.g. Ranunculus and Juncus still seem to be stalled.
Cladonia lichens are frustrating for identification because they generally can’t be ID’d to species, and morphologically the genus seems to have very clear divisions, except that those divisions apparently aren’t monophyletic. The consensus from taxon experts I tagged was to wait (probably for years) until new literature is published. I’m not going to go and implement my preferred taxonomy there if all the top observers and identifiers won’t like it, but it would help a lot of more casual observers…