The problem is to do so widely. There are already humans who believe, or were, perhaps, humans of very degenerated types who still very much believed in these things, but it was encased in secrecy. You have already seen someone in the USA who wanted to talk about some very simple facts; those of captured flying saucers made from rather regular metal being kept in a military storage.

Despite this being true, expected by the public, and fairly uncontroversial, he was instantly discredited as having "a history of mental health issues" and the matter was pushed aside. Those who do work with these things believe them to be scientific, but they prefer the general public does not know. For this reason those will not be "accepted" if seen, and they cannot be mass produced. Attempting to use such a craft, despite it being little more than a flying car, would have attracted instant attention from military, who would confiscate the craft and the person who invented it would "disappear".

The reasons for this is many, one of them is that there is an industry making loads of money from selling fuel, which may be obsolete with new technology, as well as the need for roads. One reason for taking in huge sums in taxes is the motivation that public roads must be built, the money is then stolen by corrupt officials.

These are some common ways in which the understanding that levitating devices are scientific is blocked from the public.

This is what will be handled. The groups which were a hindrance to this correct development are now removed, they are NPCs, so we can now start moving humanity in the direction of understanding what it possible with some metal and regular algebra.