I see smaller versions as being practical for off grid out in the country use with storage batteries and large capacitors used to store current, though solar cells would be better for sunnier climes.
If Return of Investment is the prime motivation then no, these systems will never be practical as a money return rate of profit vehicle. For a SHTF or just want to run a few lights and a low watts led tv out in the boonies with your huntin’ buddies out in a deep woods cabin, these might be ideal. If your combo wind/solar system keeps a few lights on when others have gone dark, yours will be the most important house in the neighborhood. No they won’t keep the fridge or heater going but they’ll keep a few lights on and power a radio and some power tools(battery operated rechargeable) and might make a difference between a miserable demise and a chance to “get over the worse of the hump” and survive.
Makes nice little turbines in kilowatt size form factors but starts becoming a hard sell after 50kw.
Company was trying to get investor funding for megawatts sized turbines.
Did a design scale up of turbine concept to megawatt output and the turbine was roughly the size and shape of the Huston Astrodome - and a lot more expensive to build.
Very short term employment after that but I at least I stayed away from scrutiny by Securities and Exchange or the bunco squad.
Oh well, at least their check cleared the bank, which kind of surprised me