An axel thingy would be something related to figure skating. I'm guessing that the axle thingy you're referring to is the quick-release.
A quick Google search leads me to believe "axel thingy" is "RockShox Maxle Lite Front Thru Axle."
OK. Modern alternative to a quick-release, particularly on mountain bikes.
Yeah. It's odd - both an axle and a quick release thing. The problem I had was that the quick release mechanism was lose (somehow I must have loosened it). I couldn't figure out how to tighten it. Turns out there's a little hex head that you can tighten. But you have to know where it sits and how to reach it. Youtube saved the day.
Those thorns makes wonsed if you have considered trying tubeless? That liquid sealant should make difference.
I have considered it but haven't gone tubeless. If I stick to the well worn trails I don't have any problems, but I've had two thorn-flats in the last couple of months when I took my bike on mowed grass trails that don't get much riding.
I've gone tubeless on both my gravel and road bike. I can't say that I've noticed a leak that got sealed just yet. When it is time to replace the tire I'm going to experiment by poking some holes to see what happens. I also need to practice with the plug-kit thingy.
I've got tubeless on my MTB. No flats so far (a few years), no plan for what to do if I get one.
No thorns here, but I used to get flats too often, drops resulted as snake bites. High enough pressures were too harsh (hardtail) and grip on wet/icy roots/rock was gone. I went tubeless with foam inserts, lets me have any psi and even lets me cycle carefully home with a flat. At the moment I have 8/12 psi front/rear. Nice for current wet slippery conditions.
Hah! I don't have tubeless on my MTB! I have tubeless compatible rims, and I think there are tubeless-ready tires, but there's a tube in there!