TBH it does read a bit like the OP has pruned some hedges, buggered off for 6 months and is now all afronted that some younguns whose “Vision” diverges from his own have started to try and build some trails along the runs he previously cleared and left…
I do understand the sentiment, I’ve gotten a bit over sensitive about other people changing trails I liked as they were, but actually those doing it are likely to be motivated by a love of riding bikes and not actively trying to ruin “your” trails…
Cheeky trails grow, it’s the nature of them, I’ve got similar concerns over “Dog walkist visibility” for my own local woods but those of us who do the digging have all agreed it’s better to have challenging and interesting trails for all to ride, which might not be there next week than a Safe, low key “yawn fest”… Basically we’ll face the challenges if/when we get them, who really want to take the default appologist position?
The fact is you’ll not stop other MTBers from wanting to build if the area has posibilities, perhaps getting them organised and dealing on some level with the FC could help…