If Trump did this, and I am highly skeptical of that, it might be about more than Biden. Ukraine is closely tied to the DNC/FBI/Hillary et al coup on the candidacy and presidency of DJ Trump.
It’s all possible.
But; undoing or uncovering the non-Biden shenanigans in the Ukraine would primarily impact the conviction of Manafort; who was convicted of long ago pre-Trump money laundering activities. Neither of us can know whether Trump knew about that stuff when he signed Manafort onto his staff, but I’d suspect that Trump would not go too far out on any kind of limb for Manafort. Manafort could have some stinky money laundering activities in his past. As for what the revelation of info would for the FBI/FISA coup effort, my feeling is that’s too far back there to be dredged up to any great effect. There is much more recent and closer to home info about to be revealed (hopefully) by the IG.
The Biden/Ukraine connection is profoundly more overt, meaning open and shut. And, that confession/brag by Biden in front of the CFR is damning. The law regards spontaneous confessions as among the highest-levels of evidence.
The flavor of the Trump/Ukraine issue depends mightily upon wheher there was a quid prop quo in terms of foreign aid withheld/released. I don’t think you or I can know the particulars at this point.
But if Trump is the de facto source of the leak, IMO it’s a stroke of brilliance.