It depends what you think the purpose of the event is. The "type battles" aren't the main point IMO. The main point is to get regular players more used to PvP. Which the event is relatively good at.
I wouldn't be opposed to enforcing the theming (for example, similarly to Parasite Paracide's restriction), but I don't think it's a failure of an event type for not doing so.
If you want players to be eased into PVP, wouldn't it be better to have them face gentler decks? I'd rather have the event be about "Fiends VS Fairies" and "Insects VS Dinosaurs," compared to nothing but "Blue-Eyes Cosmo VS Six Sam Synchro, ft. Neos Fusion."
But they didn't write anything about easing players on the previous events, only in this one (with the 5x NPC duels description). All the descriptions and advertising for this event are theme battles. Which is failing even now that it's not even telling people to use Junk/Neos, just anything warrior gets the points... they could use their tryhard samurai and still be following the rules, but.
wow
Dab