East Yorkshire reduced it from hourly to two hourly a few years ago because it wasn't viable. Viscount then introduce an hourly service on top of that, and it was somehow viable... in my experience, that is best described as "unlikely".
I suspect that whilst there are family reasons, had they not intervened, you'd have seen the service fail anyway. Just do the maths!
Selected journeys will be busy but many others will be pretty far from two thirds full. Given that many will be twirly pensioners during the day (for whom NYC pays a lousy sum), it's not the pot of gold you may think.
Do you recall the X54 from York to Harrogate? It was operated by Transdev, who then deregistered it before Connexxions had a try at it. Some of the journeys were popular (usually the mid morning run into York and an afternoon run out) but not all and as they were dominated by pensioners, they couldn't make it pay.
The X54 had direct competition from the train, on top of car ownership. In my experience, a lot of Young people are using the 28, presumably trying to meet up with friends in Pickering or Scarborough, not just Old people, and not even selected journeys.
East Yorkshire reduced an indirect service from hourly to every two hours, not a direct service. An hourly 28 is probably not viable, but an hourly X28 is probably more viable as provides shorter journey times end to end.
Again, how do we know the X28 was financially unviable for Viscount when it was only running for 5 months, and stopped running before the end of the financial year. The truth is, we never know the true viability of the X28 because of the abrupt closure.
The X28 may well have failed, but I do think an hourly service is possible along the route. A company that has the financial means to operate it and show North Yorkshire Council that there is demand for it, whilst perhaps making a loss in the short term, could give Pickering and Scarborough an hourly link once again. Viscount was not that company, obviously, they were tiny compared to their competition. East Yorkshire could do that with an X3 (the X3, 128 and X28 altogether were never going to be viable) and in fact do similar things elsewhere. If you look at the recent launch of service 15 in York by East Yorkshire, they've taken a commercial risk and judging by the significant uplift the service is getting at the end of March, its paid off.