TNG isn't actually about science, though. There is precious little actual science in the series, or even the franchise as a whole. Ironically the most scientifically grounded series is TOS because they didn't have a ton of franchise tropes to lean on and actually hired science fiction writers now and then. I remember one episode where they encountered a (Romulan?) cloaking device for the first time, a major plot point was the 2nd law of thermodynamics and the fact that such a cloak couldn't be perfect - it had to vent energy somewhere, somehow - which is a degree of scientific rigor no subsequent series would even attempt. And then in another episode they fought Space Lincoln so YMMV. By the time you get to TNG any pretense at science is abandoned for "teching the tech" and inverted space wedgies and whatever nonsense Q gets up to.

That said, B5 absolutely does wear its fantasy pretensions on its sleeve, and I think you're correct about the "forward looking" versus "backwards looking" themes. The technomages are wizards with robes and mystical incantations and everything - it's explained away as "technology so advanced it's indistinguishable from magic" but they wouldn't be out of place in any D&D setting. Mystical prophecies, gods, demons, "light vs. dark" motifs, the Minbari being so elf-coded it's ridiculous, the Great Man heroic ideal, sacred tomes, eldritch ruins, crystals crystals crystals. All the trappings are there. Crusade went even further in this regard. The hero ship in Crusade is named the Excalibur ffs.

>>[I prefer] TNG because it’s about the future, about science, rationality, open-mindedness and new perspectives

>TNG isn't actually about science

I agree with your point that Star Trek is very bad at being scientifically realistic (e.g., in its plots) but Star Trek -- at least TOS and TNG -- was very good at creating positive feelings about scientific and technological progress.

Technological progress is one of the few things that large numbers of people have become so enthusiatic about that it becomes a sort of lens through which they decide the goodness or badness of almost everything that happens. Jesus and dismantling capitalism and other forms of oppression are two other examples.

In other words, the first two Star Trek shows (i.e., the shows that Roddenberry exerted direct control over) seemed to have been extremely good at attracting people to the technophilic ideology.

(TNG is also a potent advertisement for communist ideology: Roddenberry was at the time interested in communism and insisted that money was absent (or rare and unimportant) inside the Federation and that crime and strife between people had mostly been eliminated.)