Inkitt is a goddamned dumpster fire. They straight up tell you that you have to toil away in the mines of the forums in order to get any real traction, their book cover system is somehow as rigid as a board and completely broken at the same time, and I've honestly gotten no traction on their site anyway. All that, of course, is to say NOTHING of all the skeletons in Inkitt's closet, as mentioned in that wordpress article someone else posted. It's perhaps the only platform aside from Wattpad that I've posted on where I genuinely wish I never bothered to post it to begin with.
RoyalRoad's alright, I guess. I tried getting a boatload of review swaps and after I did that, it started doing okay... but I don't really think it was worth the effort, in hindsight. You should do better if your work's in the isekai/gamelit/litRPG/etc. neighborhood genre-wise, but I don't consider it a silver bullet and I'd say Tapas has a far better community hands down. Taking a trip into the review swap section of the forum(That's right, they have an entire section dedicated to facilitating review swaps! Should've been a colossal red flag in hindsight.) is like seeing an encampment swarmed with starving artists, and it honestly makes me uncomfortable to do so. I'd just take a fire and forget policy with RR if I were you.
Controversial pick here, but I always found my analytics to be the strongest on Moonquill, though I've heard others say that MQ's kind dead activity-wise. MQ also has a self-publishing program that I personally have found to be utterly unmatched by any other site or publisher out there.