Hardware Recommendations is currently still in its early days, so its policies are not set in stone yet. But so far it looks like most electronic parts would be off-topic there.
In What type of hardware is allowed?, the strongly dominant trend is that HR.SE is for IT professionals and amateurs. Computer parts that require a screwdriver to mount are allowed — they're the bread and butter of HR.SE — but anything that requires a soldering iron is likely to be off-topic.
Stack Exchange sites are communities, and a community is strongly defined by its audience. The audience of Hardware Recommendations is IT professionals and power users, not electronic engineering professionals or tinkerers. While HR could pronounce electronic parts to be on-topic without making its scope completely crazy — but of course it would be up to the HR.SE community to decide, not the EE.SE community — I don't think it would be a good idea, because it would split the site between two distinct audiences who care about different topics, with only a fairly small intersection (e.g. home-grown IoT).
The best place for recommendations of electronic parts would be a site whose audience cares about electronic parts. In other words, the best place for recommendations of electronic parts would be EE.SE!
Do note that there has never been a ban on “recommendations” on Stack Exchange. That was a decision of Super User (mainly driven by its early moderators), first directed towards hardware and then later also towards software. There are other sites where recommendations are not considered problematic, such as Unix & Linux (but there, due to the subject matter, only software recommendations are on-topic).
The site Software Recommendations (where I have been a moderator since the site's early days) has taught us a few things about recommendations.
- Recommendations definitely can work on Stack Exchange. The fears expressed in Q&A is hard, let's go shopping! are unfounded.
- “Shopping questions” are only a small subset of recommendation questions. Obvious crap is obvious crap is easy to close.
- Recommendations do need quality control. That's not a problem: Stack Exchange already has quality control, in the form of question closure (through closure flags and votes to close) and answer deletion (through low quality flags and delete votes).
- Recommendations do need some specific quality control. SR.SE evolved some guidelines on questions and answers. It's a good idea to have clear written guidelines to show them to new users.
- A motivated community can definitely enforce those quality guidelines. There's no need to be worried about a flood of crap. The main problem SR has is people on other sites who tell people who ask bad recommendation questions to go to SR.SE — a bad recommendation question is no more welcome on SR.SE than it would be elsewhere.
- But SR.SE does have a problem: many questions go unanswered. It's succeeding at moderation, but not so much at providing answers, which is the goal of Stack Exchange in the first place! A recurrent problem on SR.SE is that, especially with questions with somewhat specialized requirements, the experts are by and large not there. SR.SE has a relatively small community; that's ok for moderation, but expert answers require a much larger pool that only sites without a restriction on the question format can provide.
Might there be something about hardware recommendations that makes them very different from software recommendations? A little, I think, because they age faster (not only does hardware age faster, but hardware recommendations age faster due to pricing variations). But not fundamentally so.
Ideally, recommendation questions should live where the experts is. For electronics parts, that's here.