They're just missing a trick, not everyone wants to migrate to v5 / "The Cloud" etc.
So many options out there for store owners, dozens of carts available, but with X-Cart Classic, at least you own it, and there's some comfort from that.
And FYI, plying us with money to place a review doesn't work.
Maybe I'm just old skool. Waiting patiently (as a lot of the dedicated XC4 folks and my clients are) for v4.7.13