I don't know if it's fair to say that it's moving away from decentralized installations. There were a lot of subsidies for home solar when solar wasn't competitive on its own. Now the subsidies are gone but the panels cost less.
In the new context a large solar installation connected to the grid is more cost effective if you need a grid for nighttime. The real question is whether batteries will make it so you don't need that. They're currently too expensive for that, but they're also declining in price. So if batteries get cheap enough that you can run your home from local panels and batteries without needing the grid, the cost of needing to keep the grid when you could otherwise not have it anymore makes the centralization lose its cost advantage.
