Dustin Poirier has never lost two fights in a row...but Poirier is 35 now. As far as official statistics go, the oldest lightweight [155-lb] champion in the UFC was [IIRC] Sean Sherk, who was 32 when he won the belt in 2005.
Unfortunately for Dustin, he has been everything EXCEPT the overall champion. He was interim champion in 2019, but lost both his championship attempts. But at age 35...I just don't know how much Poirier has left.
A friend of mine told me that in the UFC, being the interim champ means just as much as the overall champ [?], but he didn't explain why that was.
But anyway - while Poirier's personal history would suggest he would win this fight [coming off a loss], the overall statistics for 35+ aged lightweights are not that good.
I hope he wins though. I am a big Poirier fan. I had never heard of "BSD" before this fight. I knew that France had banned MMA, but that must have changed at some point in the past decade.