Exactly, you weren't going to get talented, committed smart young persons into the solar industry in the late 2000s - early 2010s, all the money was in internet tech. No solar company could have competed with the 600k yearly comps provided by companies like Google to middle-rank engineers.
Tesla and everything Musk-associated bucked the trend for a while because of the literal personality cult surrounding him back then (a thing easily forgotten by now when everyone likes to hate him), that's why his companies were still able to get young talented engineers and working them very hard while not paying Google-like comps.
Not every talented engineer is eager for the cut-throat hustle to chase a 600k comp package (which ends up at 70k when the stock implodes). I'd think it might even be slightly less common when you get into research and greenfield stuff-- you've got people motivated by a vision and the opportunity to deliver it.
Messaging like "We have the financial and structural backing to keep the project alive indefinitely" and "This is a job for life-- if it takes you 20 years to make the breakthrough, we're willing to wait" might appeal to those people, even if the compensation is a bit lower.
I agree that there are other knobs to bee turned, but housing will most probably get in the way of that, as the people earning 600k per year will chase out of the housing market the people who will go with their passion.
Similar (and related) discussion when it comes to education, people earning 600k per year will be able to provide better education opportunities to their children compared to the passionate but earning-less-money people, and if you're part of the second group at some point it will become harder and harder to explain to your spouse that your kids won't get the same chances in life compared to your friends' children because you're going for passion over money, unlike said friends.
I know that all this sounds very mundane but it's part of day to day life, maybe the Soviets had a good idea when they basically built scientists-only cities in the middle of Siberia or somewhere like that.
Tesla and everything Musk-associated bucked the trend for a while because of the literal personality cult surrounding him back then (a thing easily forgotten by now when everyone likes to hate him), that's why his companies were still able to get young talented engineers and working them very hard while not paying Google-like comps.