It's a great thing, and a great place.
But over tourism and ignorance is spoiling it. No one 'wild camps' in a motorhome or campervan, you're roadside camping. I wild camp in the hills having walked 4 hours to get there. I use my camper mainly on sites these days as it's been spoiled by the masses in the summer, and any roadside camp upsets these days. (Unless it's winter, then I've the place to myself...)
IMO there are many other fabulous places on Scotland and NC500 pedals a fallacy of being 'the best' holiday in Scotland. It's a great drive. People forget how big Scotland is - and how much diversity of communities and scenery there is.
But to slow down, potter, explore nature, visit communities, empty beaches, climb mountains, wander the woods, find local artists, local food, great whisky and gin, this is better than banging out 500miles. You miss so much. Slow. Stay a few days. Bring boots and maybe a bike.
I visited Mull of Kintyre this year - walked to the lighthouse, wandered beaches alone, had a great night in the pub at Machrahanish, pedalled my bike around Gigha, swam in empty lochs and wandered around ancient monuments, visited a tidal island, saw otters, seals and white tailed eagles, looked over the sea at Northern Ireland and Isle of Man, and tried the Campbeltown whiskies. Brilliant, absolutely stunning, and really unique trip and place. Yet it's a place so few go to, purely because Instagram and some tourist marketing strategy isn't strong enough...
I also did the outer Hebrides - oh my word there's some places there which are just amazing, but even better, not on Instagram..I could stay a month there.
I also visited Galloway - around Wigtown and the far west. Just a brilliant wee place, so much to see and do, Best whisky of the year there too at Scotland's most southerly distillery. I had a mountain to myself one day. Yet I bet most people have not even heard of it.
And my holiday highlight of this year was a winter trip to Royal Deeside - all Balmoral winter walks in the ice, hot chocolate by the fireside, empty glens and thundering waterfalls (and a skinny dip in snow melt river...)
So by all means do the NC500 responsibly - stay on campsites, buy local food and crafts.
But also come back and put some imagination to work and try to spread the tourism load, and in doing so find some really, truly wonderful places and outside the regular assumed season.