The M2 Mac Mini is $599, or $499 if you can get the education discount. There is not a (new) Windows PC in that price range that has the same performance (especially performance-per-watt) and Thunderbolt 4. The M1 MacBook Air is getting a bit old, but it’s on sale for $600-700 pretty often and will knock the socks off most PCs in that price range, especially in build quality.
Apple’s pricing gets ridiculous when you try spec’ing up with certain memory or storage upgrades, sure, and most internal upgrades are a no-go. The base models of most of their computers are incredibly competitive, though.