From what I understand the situation is quite the opposite, there is a huge pipeline of investment both in startups as well as very large corps on the development and application of gene therapy.

As anecdata, Luxturna costs north of a quarter of a million per vial, it treats a fairly rare disease (Leber congenital amaurosis). Roche still poured millions into development.

Bio-tech, specially in a Medical field, is a very difficult business. The strategy for must startups is to get bought by a very large pharma company. The issue is that these companies often run out of runway, specially when dealing with later pre-clinical, clinical, and regulatory costs.