I want to make my game prototypes publicly available to get feedback as I go along. Because its a "raw" prototype, then it's pretty much a given that it will be omitted from the "Most Recent" page in accordance with the Quality Guidelines.

So my question is, what is the ideal pipeline when working from a Protoype all the way to Release within Itch.io?
A. Keep the prototypes as Draft / Restricted, and share the project link somewhere else like the "Get Feedback" topic of the Community tab?
B. Make the prototype page public and once the game and project page is close to release, request the Itch.io support team to re-index the game?

I'm not sure where you're seeing this. Quality guidelines apply to your project page. Otherwise, people upload prototypes all the time. Even literal  homework. To wit:

Keep in mind it is okay to create works in progress, or temporary pages. Just know that as soon as you publicly publish the page ideally it’s ready for others to view it.

So it's perfectly okay to make your page public as soon as you have something people can download and play.

then it's pretty much a given that it will be omitted from the "Most Recent" page in accordance with the Quality Guidelines

That list is not curated. And those guidelines are not enforced as such, they are recommendations. Best guess, they have an automatic that filters some projects for human verification. And if the project is not an attempt with ill intent or formally wrong projects (not having files for example), they would probably index it anyway. Waiting time for human verification can be several weeks though.

project page is close to release, request the Itch.io support team to re-index the game

There is no "release" on Itch. Your project is released the moment you publish it. Oh, there is a release date you can set, but this has no practical value, unless you are a professional publisher bound by some contracts to release at a specific date. Or maybe if you have a paid game and do not want to sell yet.

You will even find "on hold" and "canceled" projects on Itch in recent. That attribute is more like a an information to players what to expect in regards to updates. Prototypes are more like test projects.

What you described is in development. But of course you can use prototype as a pre in development version. But those states are not really used accurately, nor is there an event if you change status. As I said, there is no "release" on Itch. No wishlisting. No greenlighting phase. And as far as I know, there is no difference between those states at all, beyond the fact that you can filter for them and might invoke certain expectancies.

Since there is no event for "releasing a game that was early access", you cannot request "re-indexing". There is no sorting for release date on Itch.

You can try making a major update devlog, and that might bump your time stamp for the recent sorting. But that is not guaranteed, and updating your game always has the chance to get the game temporarily delisted and on that human verification queue mentioned above. The devlogs that bump the time stamps need human approval, and that means, they might not have time for approving it or simply not approve the time stamp bump.

You should not fixate on that 5 minute fame of being on top of recent. It is often literally 5 minutes. Look here https://itch.io/feed?filter=new_games

It is as no time said. As soon as you have something to show, you can do so on Itch. But you probably will not get much feedback, no matter what you do. Most games do not have comments, nor ratings.

But Itch has game jams. Maybe you can adapt a prototype version of your game for a jam and collect feedback there.