He never says in the article to keep doing something even if it is painful. If you went for a run and experienced pain, I think it would be safe to start trying to stretch or figure out why this happens.
This is still compatible with the method he recommends here.
And your refinement of the advice only coincidentally happens to work because my injury was non-acute. There's plenty of sports where you can seriously hurt yourself if you don't know what you're doing, without any prior warning.
And the advice also only works under the assumption that you get multiple chances, that you will not catastrophically fail on your first go. All of the following sound absurd: - if you want to fly an airplane, just fly an airplane - if you want to build bridges, just build a bridge (not a toy one, that's not "the real thing", one that people will actually use) - if you want to skydive, just knit a parachute and jump out of a plane
Of course, you'll say that that's not what you or the OP mean with "doing the real thing" and they're obviously insane. But they're just edge cases to prove a point, you don't need to fail this catastrophically to cause serious harm. OP writes about someone rejecting a job that requires fluency in French, without posting any details about that job, then judges the person for rejecting that job out of hand. That is just crazily irresponsible, it may very well have been a job where she has to communicate in French with French-speaking clients, and where a miscommunication might cost her company a large contract, cost her or her colleagues their jobs, or just sink the company altogether.
I think if your advice has this many edge cases where it is harmful, you should think carefully about who you are delivering it to. I'm not saying it is bad advice in all circumstances, it might be exactly what some people need to hear. But it is bad advice to broadcast unqualified.
It shouldn’t even be a long one. I said “go run for a bit”. If it hurts at all, stop. Don’t do things that you think are dangerous. If you can’t run or aren’t sure if you should, then just walk. Maybe I should refine my advice to “do whatever is closest to the ultimate thing, that you can safely do right now”.
In hindsight you may think you overthought something and should have just started earlier but maybe you really weren't ready.
Again, don't overdo it. Do something real, look up a simple beginner way to do it, research it for 1 hour or 1 day, then stick to that simple beginner way for some time. The point is to do that thing and not get bogged down by details and researching the tiny things that only matter to the elite expert.
Also, you have to accept some risks. You'll never be fully prepared. You may hurt your ankle by running too much, but it most likely won't be permanent and you learned a lesson.
I did that, went for a run every day, overexerted my ankle, couldn't walk normally for a week and couldn't run for weeks after that, and got out of the habit of running again for a very long time.
Your advice might work in specific cases for specific people, but for others it might be harmful. It is, in my opinion, not advice fit for "broadcast": you need to know the recipient and their situation to know whether the advice will not be harmful for them.