this was all discussed at length some while ago, and it wasn't a new subject then.
There seem to be a number of basic problems;
1) there really aren't many suitable sites around, and established groups or clubs are involved with most of them
2) most land-owners simply aren't interested at all, and few land-owners have any interest in attracting third parties onto their land for purposes which yield no income or return
3) there is a genuine risk of disturbing things best left alone. I don't mean in the 'Outer Limits' sense, rather in the sense of contaminated water, unstable supports and so forth. I've upset people before by saying this, but I don't care to involve myself in digs because of some of the things I have seen on them over the years.
4) quite a few of the afore-mentioned established groups and individuals understandably lack enthusiasm for involving themselves with enthusiastic newbies with ideas which may well be more-or-less unworkable, unfeasible or having no basis beyond blind enthusiasm and a lack of solid research. If you have been around long enough you do tend to come to the view that such enterprises as exercises in the Law of Unintended Consequences, and like's Mr Murphy's well-known aphorism, results reached through such an approach tend to be undesirable.
To be quite honest, if you are going to say 'I'm not mega-serious about the idea' you are almost certainly not ready tio begin and not sufficiently committed to what such a project would entail.
Involve yourself with an established group, put some time in, learn the basics and some background, meet the people and THEN think about whether it is something you want to involve yourself in
''the stopes soared beyond the range of our caplamps' - David Bick...... How times change .... oh, I don't know, I've still got a lamp like that.