What blows my mind is how are companies turning you down? You have 20 years of experience. You can do literally anything. It's crazy that companies are so broken they pick subpar candidates over you, even at similar compensation levels.
That means nothing (and I say that as someone with much more than 20 years of experience) - unless all that experience is in exactly the area the hiring company wants - someone with 20 years of the wrong experience (cobol for example) is going to be passed over for someone with 3 years of javascript experience, if you are looking for a JS developer. You probably won't even get passed the HR person if the skills and keywords on your resume don't line up exactly.
I've often pondered on this, likely some survivorship biases involved as well.
They are repetitive and frequently off the mark. A client has issue A, and she strongly advocates for solution B1. A client has issue B, and she strongly advocates for solution B2. A client has issue C, and she strongly advocates for solution B3. A client has issue D, and she strongly advocates for solution B2 again.
She lacks the knowledge to access solution spaces A, C, and D.
People who will bring new ideas, rock the boat, offer to do the same task but in an easier way... Don't make good peons for these managers.
That's why Microsoft loves contractors. Contractors will do what they're told and have very little leverage. Empire-building managers there can easily control their contractor work force even if speed and sometimes quality is sacrificed.
But most jobs are looking for 2-10 years.
At 20+ years if you're not headhunted you're kind of screwed.
I've heard it often said that it depends on what kind of experience, not necessarily its length. Someone could have one year of experience twenty times, or be working in old tech and hasn't kept up with modern practices, costs too much to hire, or a myriad of other reasons for not being preferable over greener candidates.
Doctors, engineers, lawyers, builders, architects, brick layers, pilots etc are sought after if they have more experience