Your calculous is way off but I don't care about that, and you have a fundamental misunderstanding of Bloomberg's strategy here. Notwithstanding the fact that Biden's campaign is doing a fine job of dealing on a state by state basis, and he is most likely to take Pennsylvania -- along with the other crucial states, Wisconsin and Michigan -- this year. There are far more paths to victory for Biden than for Trump, but Bloomberg understands something essential: that if Biden takes Florida decisively and early, Trump is over.
A surgical strike in Florida is the best bet 'we the people' have of ending Trump and taking all the teeth out of his inevitable bitching and moaning.
Biden can lose Florida and still very likely win, but a decisive win on the East Coast will shorten everyone's misery. That is what Mike Bloomberg is thinking about. All the rest of this is naval gazing.
And the knowledge that Bloomberg can spend $100 mil ten times over and it won't touch him is making Trump's head explode is simply a lovely perk.
Don't think so hard: it's not that complicated.
https://medium.com/@gayleleslie/what-if-mike-bloomberg-is-a-21st-century-fdr-292c2f03bb8b