Sagat has had a history of being a great character within fighting games. Super Street Fighter II Turbo saw the old version of him reign near the top of the tier list. Capcom vs. SNK 2 saw him as one of the strongest Ratio 2 characters in the game. Street Fighter IV had him as an obvious top tier in the first version, but never saw him slide so far down the tier list in subsequent updates to make him irrelevant in competitive play.
Street Fighter V — upon his release — is one of the main exceptions. So how does he come back without becoming a broken mess? VesperArcade mentions the deficiencies in his zoning game — where the game itself sends him into very awkward spacings — but also makes a note that his movement options leave a lot to be desired in their current state.