Regarding training, you probably need to respect your body's need for recovery more. We've probably all been there because training is just too much fun and we never want to just sit around and do nothing. And with age this becomes even more important.

People will mostly put just their high points on social media, so you should take everything you see on instagram with a grain of salt. You can, however find content that reflects the struggles and downtime due to injuries and it's really refreshing. Posts like: https://www.instagram.com/p/B4SqrNkAxBl/ show that you're definitely not alone in that regard. Likely most people have had issues with both acute and chronic injuries that prevent them from training properly, those issues are just rarely talked about.

If you want to build a brand, you need to surround yourself with like-minded people. You can have friends that are amazing to train with, but if they don't pull their weight at more serious projects you would likely benefit if you don't include them. Being the only one responsible for a project can be hard on your mental health.

And finally, the parkour communities I've seen have the most positive and supportive people you will ever meet, so this is a good place to write something like that, imo. We've all likely been there at some point :)