"I think that increasing the block size will increase centralization and thus violate Satoshi's intent."

Then why did he specifically suggest that we do so?

"Segwit is just a malleability fix, it is still fully recorded on the blockchain. "

This is not true. SegWit itself claims that it enables "off-chain transactions". Those violate the definition of Bitcoin. SegWit is not compatible with Bitcoin by definition.