This can be interesting to put into your world-building.
Not just in the sense that places don't have history. Though they don't, this can be handwaved often enough. People have really poor grasp of history. Like the lines about kids nowadays have never known a time when you had to get up in order to change the channel on the TV.
In pseudo-medieval times, or earlier, or somewhat later, you could probably get away with it. Contrary to popular belief there was a good deal of technological innovation in the Dark Ages. New plows for instance, without which much of Europe was not arable land. Watermills -- the Romans knew of them, but built only a handful; Dark Ages Europe loved them and built them all over the place and put them to uses that neither the Romans nor anyone else who knew of them used them for. But the innovations didn't come thick and furious. How likely was it that you would be there when they first built the mill? (Though I remember one story about iron weaponry being introduced to England -- really ancient times.)
When you get into steampunk, things get more interesting. You have the Mad Inventor form of the Mad Scientist, but you only sometimes get people thinking about the new-fangled inventions. By Victorian times, inventions came fast enough that any adult would have remembered a time when some things were done very differently.
And if you go on, into SF -- well, I've had it noted that one thing you never seen in any SF work is a character reading, watching, etc. any form of SF. Interstellar space tends to lack innovations. Not always; Lois McMaster Bujold's Falling Free has the invention of artificial gravity, but then, do you see any other major innovations between that time and Miles's?
Perhaps there's a limiting factor. Like life expectancies. Now that antibiotics, sanitation and cheap food have gotten all the low-hanging fruit in lengthening lives, medicine is progressing rather more slowly.
If there's retrogression on some planet -- which would evade such a limiting factor -- it tends to be depicted as the medieval times were. I didn't like the sequels to Sharon Shinn's Archangel as well as the original, but I did like the way they acquired things, like electricity. And the Gabriel Dam is a major new artifact. This is rare.