For the same reason companies in the good old days at CES did the same thing.
Either their board does not exist or wasn't ready for the show.
Listen to some of our interviews with the original Atari people. They all did the same thing.
That was the 1970s, when trade shows were the main form of sharing information like this. Atari didn't crowdfund their company. While it's true the public didn't see Atari products until they were finished, they weren't in a position of being asked to pay for unfinished products. RVGS chose Toy Fair as its big coming out party. None of the potential buying (funding!) public cares about or attends that show.
I can think of other contrasts...
Atari was a pioneer, RVGS is a nostalgic copycat.
Nintendo (an old company with assets and accomplishments) innovated. They never used pieces designed by other companies. Sure, there were deliberate, strategic partnerships like the Sony chips in the SNES, but this wasn't cannibalization of off-the-shelf consumer parts. RVGS has parts of numerous established systems of the past. The "Chameleon" system appears to have more old than original parts.
Atari, Imagic, Magnavox, Nintendo, Sega, and Sony all had fan magazines with dedicated coverage to their platform. This was in the days when print distribution was the main way to communicate with players, and the material was driven by the software. RVGS made the magazine first, but plans to charge itself for promoting Coleco Chameleon material.
In the old cartridge days, you could buy them at retail all over the place, including at supermarkets, drug stores, toy stores, department stores, and mail order catalogs. They were prone to discounting and clearance, and were eventually found in yard sales and thrift shops, until eBay came along. RVGS and Chameleon are by necessity going to be internet only. The chances of finding anything Chameleon branded "in the wild" will be effectively zero. Is collecting any fun when it's just buying from a single source?
Bad old Nintendo controlled their platform with an iron fist. That worked for them for a long time, until it didn't. Software developers will choose ubiquitous, open platforms over niche, closed platforms in every instance except when they're deliberately trying to make something strange and obscure. RVGS wants to replicate the monopolistic practices of bad old Nintendo, but in a market with powerful, ubiquitous open platforms everywhere.
As others have pointed out, most successful electronic products have the hardware first, and the "suits" only become necessary to manage things if/when it blows up big. Logos, casings, slogans are nice but should be secondary concerns, after the work is done, in my opinion. RVGS has a management team, but few engineers or software developers, at least in public.
Can anyone think of an example of a successful, small business revival of an ancient defunct brand like "Coleco" is trying to pull, with or without the original creators on board? I'm not saying it can't be done, but I'm curious if I'm missing something. Examples must be credibly small businesses, Apple Computer isn't a valid answer, "here's to the crazy ones" notwithstanding.