That's not necessarily optimal. For home installs, you can overbuild panels because they're cheap compared to the inverter. Then you curtail sometimes at midday

That's not necessarily optimal. For home installs, you can overbuild panels because they're cheap compared to the inverter. Then you curtail sometimes at midday and have extra energy on cloudy days and in the morning/afternoon. Turns out that's more cost effective than sizing the panels perfectly. The same logic could apply to utility farms, because transmission lines can be expensive. I don't really know myself since I don't work in the industry, but I would not be surprised if they slightly overbuild vs. the transmission line capacity.