From what I recall reading a year or two ago, funding was pretty much 1:1 with their development costs for mRNA research over the past decade. And even if it is not 1:1, it is a hell of a lot different then the government only throwing them the $80 million or so it costs to get through trials. The $2.5 billion was not part of the purchase agreements with the US government. That agreement gave the US government the right to purchase vaccines at $16 per dose which was not too different from the EU’s price of $19 per dose.
Yes, most drugs being developed have some government funding. Moderna’s vaccine is different because it was overwhelmingly funded by the government. Pfizer charged similar rates for their vaccine but refused government funding for it. Any drug that receives government funding should be severely limited on the profit they can make on it especially if it was largely paid for by the government.