No doubt he got hired largely on account of his last name. Apparently Burisma hired multiple people with international political connections for their BoD at the time, including also the Polish ex-president Kwasniewski. But just because they accepted those positions with corresponding fat pay-checks, knowing the kind of corrupt business environment Burisma operated in, doesn't mean they were automatically guilty of corruption themselves.
You're the lawyer, not me, but it seems to me you're confusing understandable indignation about people being paid fortunes for extremely limited amounts of actual work in international business, with actual evidence of corruption, of which you haven't presented any. It's publicly known that Ukrainian prosecutors were indeed investigating corruption in Burisma, but they maintain this relates to an earlier period, before Burisma supposedly cleaned up its act and made a big public gesture towards corporate governance by appointing new internationally known people to their BoD, including Biden and Kwasniewski. I don't claim that that's proof that everything they did after that was above board, although you do imagine that people under that level of public scrutiny would carefully consider the possible reputational damage before agreeing to such positions, but it does put the burden of providing evidence of the contrary on you (or, you know, the Ukrainian and possibly American prosecutors whose job it actually is).
Of course, for electoral purposes, you don't really need any kind of evidence on this sort of thing. Putting together some not very favourable facts and suggesting that that's all the proof you need works well enough if you're just trying to slander your opponent or his family in an election. Which is fair enough by itself, as long as Trump does it with his own or his campaign's money (in that regard, it's a positive that he used Giuliani) and doesn't try to get it in exchange for military aid paid for by the US taxpayer and awarded to Ukraine by Congress.
Yeah, new fashion or not, I'm going to lay off the all caps if you don't mind, it just looks silly...
Though not as silly as the content of that paragraph. You speak about 'conclusion' as if you had offered even the slightest shred of evidence or argument beyond 'it looks shady to me'. Which makes you even less credible than the Ukrainians who at least ran some kind of investigation into Burisma.
And secondly, even if Biden actually had been under suspicion of corruption by Ukrainian authorities, still there is a lot of corruption in Ukraine as you pointed out, and it would still have been inappropriate for Trump to focus specifically on that one case. Incidentally, if that had been the case, the Obama administration would also have made very sure that Biden was kept far away from anything regarding Ukraine, because theirs wasn't a madhouse like the Trump administration where loose cannons are left to run riot all over the place.
Demanding that Ukraine clean up its act on corruption in general is one thing - and has been a message pushed jointly by the US, EU, IMF and others in the past. You know, that time which some Republican conspiracy theorists are trying to spin as Joe Biden single-handedly getting Ukraine to lay off his son, knowing full well it was nothing of the sort. Demanding that they investigate one specific case with such obvious links to the president's re-election campaign... well, in any half-way functional White House, the responsible officials would have made sure that the president did nothing of the sort. And that's without even mentioning his mention of Crowdstrike in the same call, yet another baseless conspiracy theory.
Still waiting for that evidence you've conspicuously failed to present, other than the character assassination. Unless you think that's evidence enough since anyway this isn't about anything to be pursued in a court of law, it's just about public opinion.