My two cents on DDD.
DDD's frame data is odd. He actually has a good number of decent, fast attacks. He just doesn't get anything from those moves. No significant shield pressure. No early KOs from his safe stuff. But he does have a lot of good buttons. DDD ends up playing for a bunch of single hits, hoping that he gets you off the stage where he can really shine. But its a painful process.
The problem is almost everything DDD does is safe for your opponent to shield. DDD's game plan is to make sure you don't shield. You have to use Gordos to keep your opponent from shielding all the time, since they do decent shield damage. This forces them to commit to attacks or move around them. Then you can actually play neutral, fishing for the whiffs and poor defensive options.
Outside of block? DDD has pretty solid numbers.
On the ground, his u-tilt and d-tilt are frame 7 and 6 with end lag in the high 30s. That is right on par with Wolfs tilts, for comparison. Grab is frame 8, with decent range, but grabs suck in general in this game. You aren't surprising anyone with a dash grab from DDD!
From a short hop, he has a Nair @ frame 7 or a Fair @ frame 13. Worst one you would throw out in neutral is Bair @ 17. End lag in the teens. Only slightly slower than the aerial powerhouse; Ike. Its only a few frame difference.
But heaven forbid your opponent shields...
He does have some frame problems on shields;
1) His tilts suck on block. Dtilt and Utilt have speed, but no range, so if your opponent blocked, you are probably getting hit. F-tilt has the range, buts its frame data disappoints; with 12 frames to start up, 10 frames of active hit box and ~20 frames of vulnerability at the end. You have to be careful with it. Thankfully it has range, but a jump out of shield nullifies it handily. Online warriors love this move, since the lag makes it appear much safer than it really is. Most characters can punish it on block in the absence of lag.
2) Inhale is the real disappointment for him, frame data wise. 20 frames to be useful. Takes almost a second to wind down if you whiff or if the opponent shields. Still 30+ frames even if you snag something. Most projectile users can just shoot a second one to keep pressure up. Better off using aerials to cancel projectiles or shields to approach. Inhale just has such terrible frame properties that it is rarely helpful for shoring up what I think its design was supposed to do; help approach.
3) His disadvantage on block with aerials is considerably higher compared to top tiers too. You aren't pressuring shields without Gordos. Even with a Gordo + an aerial, you don't have great follow ups to a block, so you can't immediately pressure. 90% of the time its better to just dash back on block and reset neutral (Zaki does this a lot!). I wish Inhale was a command grab...
But his real weakness is reward; not risk.
The big difference that DDD has to the top tier threats isn't the frame data. Its the reward you get from his attacks.
DDD's safe moves kill at higher %s than top tiers, despite being a heavy. Its a problem, since you don't have to respect DDD's hitboxes like you do with say... Ganon. His u-tilt isn't killing until like, 130%? D-tilt doesn't send people far enough away to put them in compromising positions. His Fair isn't going to hit outright until really high %s. His Nair sends people out at a non-threatening angles. Up air doesn't end stocks likes Ike's or Palu's can. You really have to build up %s.
Because his safe stuff isn't threatening stocks, your opponent can usually play the long game since you don't have options outside of Bair or Jethammer to end stocks quickly, which are both easy to avoid on stage. Bair fishing is obvious since the DDD is too slow for RAR to catch you off guard and Jet Hammer only punishes obvious approaches or be used at the ledge. DDD becomes almost totally reliant on edgegaurds and ledge traps to take stocks. He is pretty good at this, thankfully, but it creates a big hole in his game.