A couple farms that barely make profit are already going to be unattractive to investors. It really doesn't make much difference to future investment. There's not a massive sea change between 1% profit and 2% loss, they both suck. Investors are going to focus on the higher profit farms no matter what, ones that would still be positive if they lose 3%.
Other things can go right or wrong and change the numbers by a couple percent. That risk is pretty normal. It's not something wild.
And any farm that's already running or even half-built is still going to be finished and maintained and make as much power as it can. Once you already spent a big percent of the budget you're not getting it back, and the ROI on the remaining spending is very high.
The challenge is that your neighbor building a wind farm next to you changes your profitability. That uncertainty isn't priced in. I think you're really assuming someone here is saying "stop building wind farms" vs "this is a problem investors in the space will need to account for as this scales up more"