The main difference lies in the fact that SegWit aims to restructure the block space to allow more transactions per block, while Unlimited aims simply to raise the blocksize to allow more transaction.
You seem to be misstating your summary.
Bitcoin Unlimited attempts to change consensus thresholds. That's no minor or inconsequential change.
Mate, could you please explain me ? What he said is false you said. You did not talked about SegWit so his description is right, isn't it ? And for Unlimited, they want to change how much is required to apply an hardfork or a softfork ? That is what I understand by consensus thresholds.