The BTC about 500k USD worth, of which 200k got taken as VAT, was used to develop the technology for the first 2 years. Only in the last month have the IOTA foundation been able to legally access the money donated to them by the community.
As opposed to say, tezos which has 232mil to develop their self-governing token. Additionally, "the founders get 8.5% of the fiat proceeds in cash in addition to 10% of the tokens"\
Iota has bigger problems,
... which isn't actually so bad when you think about it, as long as those BTC all went to their foundation.
Iota has bigger problems, like pretending to be more efficient by using a DAG, when in reality everybody still needs to see the whole tangle to verify transactions.