There are a few Cell papers on heritable RNA-mediated behavior change in C. Elegans using siRNA[1] and piRNA[2], both with strong evidence. While the author may be a crackpot and the specific ideas may be wrong, there is strong evidence that RNA-based memory exists in some creatures.

[1] https://www.cell.com/cell/fulltext/S0092-8674(19)30448-9 [2] https://www.cell.com/cell/fulltext/S0092-8674(19)30552-5