We do have floowandereeze which is a Tribute deck that can be considered playable in context of modern Yu-Gi-Oh. However, True Draco and Monarchs aren't all that playable, and Monarchs even less because of their lack of synergy and higher vulnerability to hand traps. Both of these decks have longer-lasting floodgates and they generally rely on floodgates unless they utilize a engine that is very much compatible with them and of course the Extra Deck, and that is what I'll discuss here.
I can't speak for True Draco, but Monarchs do have other options like playing with Isolde engine, Dogmatika engine, or even Libromancer engine and those engines require dropping Domain in favor of higher ceiling and more consistency, and back then in 2016, you still had to sacrifice Domain floodgates if you want higher ceiling and consistency. On the Isolde engine, you basically run thing like Neo Space Connector, Fire Flint Lady, Small World, and your end goal is to activate Zaborg the Mega Monarch turn 1 or turn 2 (with Escalation of the True Monarchs). On Dogmatika Monarch, it's equivalent to the old concept of Burning Abyss Monarchs where you use Burning Abyss to grind, and to use Monarchs for other things, but it's more about hurting the Extra Deck and yes, Dogmatika Monarch do run Zaborg the Mega Monarch. And then, Libromancer engine can set up Extra Deck plays easier than the other engines, and inherent ability to search either Ether or Zaborg the Mega Monarch. There's that 60 cards variant shared in Monarchs discord where you use Generaidors and Eldlich to grind through as they both can be used to generate tribute fodders too.
In addition to the above, Domain Monarchs have dropped Edea/Eidos due to their very nature of being hurt by hand traps in favor of things like Kashtira, Mithra, Sakitama, and Anchamoufrite. The reason is that they're chainable, inherent summoning capability, and in some case, can even shut off hand traps. Sakitama can shut off Ash Blossom by going into Chain Link 2, Mithra can shut off Ash Blossom and Infinite Imperance by going into Chain Link 2 and summoning a token at the same time, etc. However, they still don't have the benefit of additional extenders and consistency offered by the Extra Deck variants.
And now we have a situation where floodgates are universally disliked, and the most supported variants (most directed support) are Domain and True Draco which utilize floodgates. And most people simply do not want to see floodgates being supported. So, that means if those decks are to be supported, but yet wouldn't be viewed in a negative light, they definitely would need to provide support that changes the original intention of their support. That means new True Dracos supported as a deck would not be compatible with floodgates, and Domain of the True Domain would not be supported by new support. But, for them to be playable, and given the nature of Tribute Summons, they either have to be insanely busted or they are almost always bad. On the Monarchs side, it's easy to think of support involving continuous spell/traps that generates token, link-1 summons akin to Sky Strikers which allows them to search Monarchs and interact with opponents during their turn akin to Escalation, and all of the support synergizes with each other, and this allows them to play through multiple hand traps with ease. Of course, that level of support would put a spotlight on Zaborg the Mega Monarchs and Majesty's Fiend, but arguably, it would be fine if they do end up getting banned if that results in Monarchs being playable, but interactive.
I'm not sure how True Dracos should be supported. So, I can't talk about the most ideal support for them.
Morganite doesn't really work in Monarchs because it does nothing going first and it stops Ether from being useful while in case of Domain, it shuts down Mithra the Thunder Vassal. That little guy wouldn't work because it doesn't fix the fundamental problem of Monarchs lacking synergy within itself no matter the build.