I don't think Wingly would ever 'harm' the income from flight schools.
Have you asked a flying school operator their opinion on this? They are at the center of the industry, and best positioned to form an opinion.
Every time a fare is paid to be airborne, and it was not in an AOC aircraft, an AOC holder lost business.
If you want to go on a quick jaunt around the local area, and are happy to just do some sightseeing, then you pay half the price and go up with Wingly. You may then decide you enjoyed that flight, so you book a proper trial flight and get hooked, then complete your training with that school.
Or, also very possible, the victim buys the flight with the Wingly chisel pilot, and due to that unqualified pilot's inexperience, has a very scary flight, and decides it's not for them, when in the company of a properly qualified AOC pilot, the flight would have been a positive experience.
I cannot deny that there could be a rare combination of well experienced pilot, suitable plane, well executed flight, and right people combination which could make this scam work, and even then, it's still stealing away needed work for AOCs, but on the whole this is a horrible idea, and I hope it is squelched before someone gets hurt.
For those new pilots who think this is a suitable way to supplement their flying, will you still think that when there are no jobs available for you as a new CPL at an AOC, because these parasite organizations have redirected potential customers away? Do you expect the AOC will hire you, when they realize that your flying was supplemented by this chisel flying?
I have a good relationship with my local AOC's, though no financial interest. I own and regularly fly three planes. When the occasional person asked if I can be hired, I direct them to the AOC. When an occasional friend asks to be flown somewhere I sometimes agree, and there is no cost to them. Thereafter, I donate the operation of my aircraft to my local volunteer fire department for searches which otherwise could not be conducted safely.
I realize that the early years of flying are expensive, we've all been there. But you don't support the industry you're trying to join by undermining it, exploiting a grey regulatory zone, and funding a third party outfit who has no interest in supporting GA.