People don't gimp Diddy because quite a few characters in this game just don't have options for gimping. It's not "easy" to gimp when none of your moves have lingering hitboxes and/ or have vertical knockback that allow Diddy to simply up b again.
How many other characters have a 4 frame up air? It was a big nerf in knockback and frame data. But it's still incredibly fast to come out and helps Diddy maintain stage control as well as gives him a follow-up option in 3 directions with forward air and back air.
Diddy Kong is still a character who has combos, incredibly fast aerials, KO setups, and an incredibly strong neutral tool in a game where 80% of the cast have one or none of those things. I would say he's still in the top 10 range. He's closer in power to Fox and Mario now than he was to Sheik, but I still can't see him not being in top 10.
And I wouldn't mind reverting the nerf to endlag on his throws. Grabs are basically Diddy Kong's ground game, as annoying as up throw up air/ forward air can be.
Most of the cast can Gimp diddy kong.
In regards to gimping, if diddy kong doesn't have a second jump and he gets hit out of barrels, then he has to charge. sure he can hold charge for awhile, but he is in the prime position to be hit again. He is one of the easier characters to gimp. Not as easy as luigi/Bowser, but on the same level as characters like Fox, ROB and Pit. Predictable recovery, but ways to get around being gimped. All the top tiers have the ability to easily gimp diddy kong, as well as a fair number of the High tiers and a scattering below that. He is very good compared to the majority of the cast, but not when comparing it to the top tiers, and on par with the high tiers.
High tiers like Pit have a strong combo game, fast projectile, strong smash attacks and a good recovery. Pit also has moves with super armor and fast powerful aerials.
Mario, with a 7-12 placement has a great combo game, pretty good recovery, Strong kill potential, damaging aerials and a reflector and air staller.
KO setups are good, but not great. You have to get the set-up first and at a very specific percent kill them. he has no throw combos that kill, unless on dreamland on the top platform. He has trouble killing without the setups, and other characters don't need setups.
Even though Diddy has good kill setups, he needs more work then most high tiers to get it. Sure banana is a great kill setup, but there are ways around banana. not always but there are ways.
I agree with the neutral and combo game, that in coupling with the banana are his greatest strengths. but kill setups are both a gift and a curse. I am not saying he is bad, he is quite good. I am just saying that he can't compete with the top tiers anymore, (unless your ZeRo) and he has trouble with some of the high tiers now. A solid 16-12 I would think but I don't see him as seventh when the first patch brought him down to fifth and that patch was small compared to the second.
Also, most people think Fox is a contender for top 5 if shiek gets nerfed.
Do you think he might get an Fthrow buff? like maybe it will kill 10% earlier, it kills at 155% now with bad DI.