Don't take this answer as an explicit 'no', but maybe instead a collection of reasons why this isn't a cut and dry 'start the thread now' sort of deal.
I am going to be brutally honest: the quality of such a thread would be quite bad given the standard of competitive player we have here. There are some people who know enough to correct the mistakes of absolute beginners chucking their teams up on the RMT area, but overall, I'd be very wary of any competitive advice given to me on PokeBase; and naturally, I'm going to project that onto the newbies who come looking for advice without the foresight that somebody like me has got. (Not that I'm a fantastic competitive player, either!)
I understand we are never going to improve in that space unless we have the infrastructure to achieve it, but I already think that the RMT section as it stands is flawed. I think the wise thing to do is make real improvements to its structure and 'quality standards' before we add more stuff to it. If there is at least a good foundation for skilled players to use the area, then community-contributed sample teams could work; but as things stand, I don't think I'd personally ever be happy with the teams posted, so I'm reluctant to start things right away.
In theory, a workaround like this would work...
mods should allow users that have experience about a certain format, regardless of their points, privileges, etc.
...and the way I'd suggest we enforce it is to have prerequisites in games played + ladder stats, which makes it easy for people to see a) how good the players are at a minimum and b) how they can prove their own skill. It also removes the subjective element of mods having to decide if people are good enough (which I have no interest in doing, because I'll make everybody hate me lol).
However, this workaround just comes back to the original problem that there aren't many good competitive players here. If we made a requirement like "prove you have an alt with >80% GXE and >100 matches played in your chosen format" (which is similar to suspect test reqs on Smogon), then the thread is going to be quiet, and we're going to have no teams for the vast majority of formats. There's also the problem of cartridge formats being difficult to verify and make reliable standards for.
There is also this point PX brings up.
We could do this sure, but smogon already does this, and they get more good teams then we do.
The reality is that Smogon is always going to have better competitive players and better advice than us. They're a bigger community, they're focused entirely on the competitive scene, and they run half the formats people play. I genuinely believe that if we worked for it, we would have a pretty good community of competitive players here; but even if we did, it would just be topped by whatever Smogon has got.
In the same way Serebii's existence doesn't mean Pokemaster should quit running PokemonDB, we shouldn't give up on providing competitive advice just because somebody else is already doing it. But it's a plain truth that anybody smart is gonna go to Smogon for sample teams before PokeBase.
It'd be cool to run the thread anyway, for our own community if nobody else; but before we do, I think we need to reach a point where skilled players will find the sample team thread/s and want to make content for them. That starts with changing the RMT section from a list of disorganised, uncharacteristic, and low-quality "Rate my very first AG team with Flygon and Umbreon on it" posts into a community of half-decent competitive players sharing knowledge with people who've at least got a foot in the door.
Again, this is a popular suggestion and we'll do it if people want it. I just think there is no point in having the thread and letting it be filled with posts from people who think they're better than they are, or enforcing skill requirements and letting the thread die an early death. I'd want us to improve the RMT section first, so that second option becomes genuinely viable. (For context, I would not put sample team thread/s on the main section because there's enough clutter there as it is.)
Feel free to leave your thoughts below.