Did anyone here get noticeably faster after raising stride rate?

Yes, although mine was more of a gradual change.

I have a low stride rate (~160 at easy pace). Is it worth fixing this?

No, not any measured improvement. But I did feel a difference in efficiency and just being more relaxed while running. It was early on in high school when I didn't know any better. I trained with an older and taller runner, ran with him on every run and just matched his stride.

I increased my regular/distance run stride rate from about 165 to 180. No, I didn't get faster, but the legs did feel better after runs.

In early high school I had a very low stride rate (ie. below 80) and saw a marked increase in performance when I honed in, jumped up to 90, and focused on straightening my back. However, I was also doing strides, increasing my mileage, began lifting, and just growing the way young people grow, so I doubt it was solely the increase in stride rate.