Do you work on your mobility much? From what I’ve seen, mobility (like core) is another boring are of focus that is left until last, if completed at all
When myself and Arwel went to Heavenly Fitness to help them with their strength and mobility, Arwel explained how he focuses more on movement flow. This improved mobility and strength by something call sarcomerogenesis (building muscle mass longitudinally). This creates a more stable change in mobility. Stretching wares off really easy
Give it a go!