Easy answer for you. As IG-11 says “Species age differently”. We now have no idea how quickly they age in their later years or when Yoda became a Master in canon. That part has been wiped away.
If your heart didn’t melt the first time you saw his face you have no soul. I think too many people hate on him because they think they can’t like anything Disney puts out in Star Wars, and they see the widespread love for baby Yoda as a second Reylo. His role in the show is really well done. He was there enough to stay at the forefront of people’s minds, as he is the second most important character, while not being overused just for his cuteness or for humor. His use of the Force was also well done, making sure to show the physical toll it has on him whenever he uses it too much.