What about it? Minecraft isn't a game that requires a high end processor. All of those CPUs should easily exceed the 60 FPS capabilities of the average screen unless you're using a mod that is causing performance issues.
You'll need to be playing on a screen rated at a higher refresh rate than 60, or the extra FPS is going to be mostly irrelevant. If you're playing at a higher than 1080p resolution, that too will put the burden back on the GPU, again making any difference in IPC of the CPU irrelevant.
If you plan to do any editing or other rendering work with your recorded videos, the 6 core 12 thread Ryzen will run circles around any i5 CPU on the market, not to mention the smoother gameplay while recording.
Who cares if you have high FPS if you:
#1) can't see them on your screen
#2) can't record them in your video or share them with the same high frame rate
Subjectively, the Ryzens are giving people smoother game play experiences. Whether this matters to you or not, there is also the reality that, in most games that are well coded for multithreading, i5 CPUs are being shown to run upwards of 90% CPU utilization, meaning, they have little left to give, performance wise, so not only will the Ryzen CPU give you performance that you probably won't be able to differentiate from an i5 CPU in Minecraft game, it will perform better on newer titles, and be significantly better for any content creation you may do with your recorded videos.