Worse are the "best explanations" that get adopted as if they were real observations with militant fervor, something we're seeing with Dark Matter and Energy today. It's gotta be difficult to make progress sometimes when most of your field insists that their best theory must be the correct one.
Please. Millions of dollars are spent every year researching alternative theories and modifications to GR that eliminate the need for Dark Matter and Dark Energy.
The problem is, and has always been, that these alternative theories are never as accurate or precise as GR and their observational evidence is never as good as what we have for DM and DE.
It's not a conspiracy that scientific consensus is that they both exists, and no one is preventing research into alternatives being done. Significantly more money goes into research that accepts their existence, yes, but that's because most scientists do as well. What outcome do you want? To force scientists to work on theories they don't put any stock in? There is still plenty of interest in research papers written by people advancing alternate theories. Good ones are widely read by the entirety of the community, but you make it sound like the scientific community is actively suppressing anyone from researching anything that casts doubt on the existence of dark energy and dark matter, and that's just not true.
It's not a conspiracy per se, but it fits into a realm where virtually every single documentary about space these days are making overt or not-so-overt claims that it's absolutely real and we're not even considering other possibilities. Of course we are, but that's not how it gets presented by the vast majority of "television physicists" and I find most documentaries about space completely unwatchable these days. Usually it's presented with unwavering faith that dark matter and energy exist, if only we could detect it. The more humble approach would be "95% of the universe is Dark Matter and Energy, unless one of our assumptions is wrong and we just don't know which one yet". That's honesty you just don't find much in media for public consumption, and if it's wrong (I'm not saying it is), then millions of bright minds are being led down the wrong path. I'm just hoping for more honesty about what we actually observe or what we desperately want to observe in popular (scientific) culture.
DM and DE matching observational data is like a ML model match its training data. Okay sure, that's necessary, but it's not sufficient to actually believing they're a good model.