RGB pre-dates Taro, as Taro was basically copy pasta of RGB (big drama when they announced it, internal name was CMYK in contrast to RGB that they copied). I imagine Tiramisu having both is their signaling neutrality.

I think these things are pointless, centralized tokens don't need decentralized networks, particularly where they're competing with more efficient centralized platforms. As a Lightning Maxi can be at peace with them since they are opt-in and would still pay me to route them without any additional overhead.

I don't think shitcoins on Lightning is as much as an "if you build it they will come" thing, but rather Tether via its venture arms and other means spray and praying a bunch of different protocols with the expectation one or more will stick and increase their distribution. There was a 3rd one that died on the vine, Omni, the invoked the Omni brand of old but for Lightning.