In Dragon Ball Super Episode 89, Roshi got some action for the first time after resurrection F, and this gave us an idea as to where he currently stands in terms of power.
It was a really funny episode, Yurin who was in the crane school back in the days, came back to seek revenge, as Tien never agreed to fight with her. Master Roshi saw through the wickedness and was thus being extra perverted or maybe he didn’t, he was just being himself. This scene really cracked me up; Goku never breaks the bro code!
So, basically this Yurin girl mastered Witchcraft to take revenge on Tien, she gets Tien’s student as well as Master Roshi under her control. As Master Roshi was still playing around with her in the name of fighting, she was able to catch him off guard.
Now, Goku and Tien were easily able to stop the students, but the case was not going to be the same with the master. Because he is the same guy, who built the basics of the best warrior in the world Goku, this is the same human who displayed the biggest feat in the Dragon Ball days by destroying the moon, this is the guy who was able to defeat The Great Ape, an Ape that had the potential to take down the entire planet, this is the guy that grabbed 18 just like that, he is the Master who invented The Kamehameha Wave and that is the most iconic attack in the history of anime and the world of fiction.