You probably could fix the issue even slightly by reducing the render distance to around 16 or 12 chunks.

I have a GTX 970, 16gb of RAM and an i7 4790k CPU and found that this works, sort of. I still get lag spikes on Java MC especially when the weather is rain where there is much more animation going on, but I presume this solution would still work for other people. And if you care about mods, use Optifine.

In the end this does not affect me because the version of Minecraft I frequent is bedrock edition. It may not have all the mods and update contents Java MC has, but in terms of vanilla MC, bedrock edition appears to be a close comparison, but just runs a lot better and at greater rendering distances without any modding necessary, plus it's crossplayable on 5 platforms. So there's your other option.

Are you using version 1.13? I notice tons of lag spikes when I use 1.13 or 1.14 snapshots, so maybe your solution is to use 1.12 or below.