Decline in Races - Why is this happening?

Many will have seen a recent announcement that the Highland Fling maybe following the demise of so many other races with even the Mont and the Kowalski coming to an end this year. I'd be interested in what people think as to why these things are happening. Is it:
1. These races are run for profit and not volunteers and therefore are prone to declines in sponsorship?
2. That people are changing habits and want to do more downhill when these races are marathon by nature?
3. That we're not promoting the sport enough?
4. That the races were just not that enjoyable?
I get a lot of stick from friends as I like a bit of distance in preference to jumps in my ride but then I've had enough crashes in my time to know what I'm capable of. Are the decline of these races a reflection of fashion?
Anyway, I'd appreciate your thoughts.

Here is the recent annoucement made by Wild Horizons: (https://www.facebook.com/wildhorizons/)

Future of Highland Fling & Bundy Run Events

For over a dozen years The Highland Fling has been one of the largest and most iconic mountain bike events in Australia - bringing together an incredible community of riders, supporters, sponsors, local community groups and local businesses to celebrate a festival weekend of all things MTB.

In 2015 we grew this weekend to include the Bundy Run, and in doing so grew our community of outdoor enthusiasts. This young event attracted a new outdoor audience and excitingly saw a solid increase in numbers year-on-year.

The Highland Fling has put millions of dollars into the regional economy and has contributed over half a million dollars to local community and charitable causes. The Fling, as it is affectionately known, has long been the largest fundraiser for many local community groups involved.
The organiser, Wild Horizons, is Australia’s longest established adventure event organiser and has, for 20 years, worked across NSW, interstate and overseas on such events.
2017 should be the 13th running of the Highland Fling weekend. But the number 13 is living up to its reputation and the future of the Fling, along with the Bundy Run, is hanging in the balance due to a variety of reasons. Key amongst these include the loss of a couple of key sponsors that impacts the viability of the events. Added to this is the continuing lack of support from local government. This has been a thorn in the side of the event for many years despite it being, for a long period, the largest sporting event in the Southern Highlands region.

We’re still searching for replacement Sponsors, investigating additional funding, and looking at what else we can do to make these events happen in 2017. What we won't do however, is bring an event that is anything less than our best. We also recognise that in recent years many of the big MTB events across Australia have stopped being run for a variety of reasons and we are keen to ensure the Fling does not follow this path.

We’ll keep you updated with a decision in the coming two weeks.