What you say has some justice, but is far from the full story. When all is said and done, most people labelled "crackpots" will not
be vindicated by history. Furthermore the path to discovering better future paradigms tends to be laid down by people working under current paradigms. Currently accepted paradigms may be imperfect, but they got to being currently accepted through a testing process that is pretty good.
I'm saying (among other things) that it is good for all of us to contribute to the testing process. That doesn't mean that we should entirely discard the results of other people's testing!