If they‘re different engines there‘s more to do than copypaste. They could also be working on different changes like to the queue system before the merge. It‘s also possible that the PvE won‘t be fully out when it releases, think I read that they plan to give updates to it in form of new missions etc. They‘ll have their small team prolly focus on that until someone tells them to merge.
The fact that none of this is clear enough or that they don't even know themselves is part of the problem. This and Diablo 4 seemed pretty rushed and in response to how bad last Blizzcon was. People getting all upset about it being leaked, but that really wouldn't have mattered if the substance was more exciting itself. You really don't see the same sort of confusion and disappointment following the new WoW expansion announcement, since we have a pretty clear idea of how it will work, when it is coming, etc.
Stale is the best word I could describe it with. Was interesting watching a bit in the past, but you certainly don‘t need to see more han a few games per season since they‘re all mostly the same games with same heroes. You don‘t have people famous for their heroes in OW like in LoL/Dota, like someone being a godly Genji, since everyone‘s forced to play the same meta to have any success. Think the OWL shows best how badly they balance it, idk about LoL but Dota metas never never are that restrictive, and due to banning phase when picking they can directly exclude what hero will be in the game.
Yeah, there's not enough different to where I would want to regularly watch it.
Meta in LoL can probably be a bit more restrictive than Dota, but it's still 10x more deep than OWL has ever been. Plus it changes so often that even if there's a distinct meta it doesn't last an entire damn season. People still have their pocket picks or unconventional strategies that work. OWL games will have people trying weird shit for a single minute and when it fails they just default back to the same old shit because it's "the best".
There's also the issue that the entire esports scene was manufactured in the first place. Games like CS/Dota/LoL had existing fanbases with competitive scenes that went back years in many places. It just seems rather fake, and a shrewd business move on Blizzard's part in order to capitalize on the game's popularity and the type of structure that existed for other games.