Go look at the Sweet Spot Progression thread, and I think you’ll observe that for many self-coached athletes, following basic endurance training concepts and achieving success is actually quite simple and straightforward. On these forums I believe some overrate the benefits of (adaptive or not) structured plans that look ‘more interesting’ and/or accept ‘science based coaching principles’ without reviewing the science, experimenting, and reviewing their own results in response to widely acknowledged (‘science based’) training principles. In addition I believe some underrate their ability to adapt/adjust efforts by listening to their body.
We all need something to believe in, whether that is self-coaching using the fundamentals of endurance training, using templated plans you buy (not rent) from respected coaching companies, TR’s templated plans and machine-learning adaptation, or hiring a coach. Pick an approach, don’t be afraid to experiment, and don’t be afraid to expand your options and try a different approach.