That was the brilliance of Yoda as a character. The moment Luke met Yoda was when his Jedi training began. He was testing Luke's patience and selflessness. Would Luke be patient and helpful to a seemingly innocent creature? This is a test of Luke's maturity to see if he will set aside his own quest for a Jedi Master and help a total stranger, which is what a Jedi would do is to help those in need, even if it's a personal inconvenience. The moment when Yoda turns off the act and Luke realizes who he's talking with, is a testament to Mark Hamill and Frank Oz being able to convey such complex changes in demeanor from a puppet. It will always be one of the greatest moments in an already incredible movie.
People dislike Jar Jar not just for being goofy, but because he has almost zero agency in the story. I remember watching TPM opening day and thinking it was really strange that Boss Nass would promote him to General. Speaking of, where was he during the battle? Then right before the battle between the Gungans and the Droids I half expected that despite Jar Jar being nothing more than a jester up until that point, that perhaps he might actually turn out to be a decent fighter, or at the very least, credibly aid those fighters more capable than him. The fact that he tells his fellow troops to stay steady when they began to get restless and I was about to abandon my dismissive attitude because we were about to see some growth.
Though what ensued was a nonsensical series of accidental victories that was so over the top that it couldn't be over fast enough so we could get back to the duel. Humorous characters can punctaute and give levity to an action sequence, but when all the character offers is humor and has no contribution other than snarky commentary, or adds inconvenience to the protagonists, they likewise become a burden to the audience. Think about it. If you were in a life or death situation and your friend did nothing more than quip sarcastically or actually got in your way instead of trying to help, you might just be inclined to use them as a human shield against gunfire. Jar Jar was a mess, but his contributions to the battle did little to win the day when it was Anakin knocking out the control ship, accidentally mind you, that won the day in that battle. It's not victory through credible action or intelligent strategy, it's victory through sheer dumb, and I emphasize dumb, luck.
It would have played well even if the Gungan Army saw the kinds of destruction Jar Jar's antics caused and they pulled a Goonies move and asked him to complete a task, knowing full well that he would break, scramble, or somehow mess up their opponent's tactics. The same way the Goonies asked Chunk to hold the framed map, being fully aware that he would shatter the glass and they would be able to free the map and the copper bones.
Say what you want about the Ewoks, but they did use the terrain and weapons they used the terrain, which gave them a tactical advantage against the Empire. While it would have been cooler to see Wookies in that battle instead, thematically they serve the same purpose. By contrast, the Gungans left their own terrain to fight a battle in a grass field, rather than try and draw the battle droids away from the city and closer to the water, which would have given the Gungans the upper hand.