I think it's much simpler. Maduro became a fixation for Trump and the republicans mostly for ideological reasons. It's the same reason he rolled back normalization of relationships with Cuba under Obama. Venezuelan oil is critical to the Cuban economy. Cuban votes in Florida are important for republicans in Florida. Removing Maduro has many beneficial side effects at a very low cost. They might end up with fresh oil supplies, critical minerals, a more friendly regime, and it send a strong signal to countries like Panama, Cuba, and others that all are under a lot of pressure from Trump already. And they get to send back a lot of Venezuelan refugees.
The oil is probably not that critical. Over supply would actually be bad for US producers that are currently extracting at a relatively high cost. Investing in Venezuela sounds like a high risk type thing. The country has a history of revolutions. There's no guarantee that any investments today are worth anything in ten years. I doubt much will happen there.
This is about opportunism. Maduro was weak. Taking him out creates opportunities. Trump can score some points, send back some refugees, please oil companies, and put pressure on other countries in the region. I wouldn't credit him with any kind of long term strategy or vision. I don't think he actually cares what happens in ten years. And I don't think he cares about the significant international/diplomatic cost either. Some bridges were burned yesterday on that side. That might actually create problems elsewhere.