Which makes sense, things that sell well also are more likely to be pirated. Has it been shown that piracy causes sales to increase? I've looked around but I haven't found anything reliable.
Have any peer reviewed papers supporting your claim in a broad market and timeframe? I find zero.
[1] https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2132153
Some people want it to be, but it isn't.
There was one (not replicated) study suggesting that people who consumed more music tended to pirate more, but that's a correlation not a causation, and it doesn't follow that they would not have purchased or subscribed to even more music if the piracy option had not been available.