I would go as far as to say that 3 on 3 hockey is more entertaining than 5 on 5, but it sort of loses the entire point when you reduce the playing area of the rink so much. There's more players per m2 there than in regular hockey.
I guess you're trying to minimize the differences in skating and reduce the number of players so that the difference of depth doesn't play that big of a role, so you could call it an attempt. But does it actually work? Looking at the scoresheets, I don't think it makes any difference.
And if it doesn't, why not make a proper tournament at this age bracket?
And how is this popularising anything if none of the games are even streamed?
The problem with the difference in level comes from the qualification and allocation format using a combined men's and women's U18 ranking. While some countries decided to go with their strength and picked their team accordingly like Italy and Hungary, others didn't. Spain and Chinese Taipei have stronger women's programs at youth levels which explains their high ranking but decided to go with their men's team. If Latvia had picked the women's tournament, I doubt they would fare well.
Another example. No matter which format, Korea men's team wouldn't have a shot at a medal. However their women's team may have a go in the 3x3's. That's why the men's team is being sent to the slaughter.
There is also an issue with this format being new to almost everyone. Unlike 3x3 basketball which has history, that form of mini hockey didn't develop organically. The GBR coach admitted having no clue when beginning their first camp last summer, being even reluctant at first. So in that case, I guess most teams didn't prepare accordingly and rely on existing individual talent more than anything else.
A tiered event would make sense to avoid those scores but is not in the "Olympic spirit". The idea here is to bring in as many nations as possible. I don't think watching Nigeria getting trounced in curling makes any sense, yet here they are. And thus despite ranking rock bottom in the qualification process. It would need to be an IIHF tourney or a regional event like the AWGs. Now the question is whether or not MNAs are willing to go full on with 2 programs every year when financially most of them barely get by at the moment and the IIHF seems to be looking more towards women's U20s as their next step (U22 would make more sense to me but that's another topic).
As for the lack of coverage, I already said it's ridiculous. I don't think installing a single camera at one end of the ice to show some of the games would have been a huge effort per say.
I'm not saying this is the solution to every problem hockey is facing. But such events allows experimenting with new things without anyone having to make any long term commitment. If it works, great! If not, we move on! Sports have been evolving constantly.