People forget that Rebirth wasn't that popular when Verdansk was around. The reason Rebirth got so big is because the Caldera launch was an absolute debacle.
The map ran like absolute GARBAGE on consoles, especially PS4/XBONE. Graphics were so fukked up, you'd be running around half under the map. There'd be open sight lines and when you went to shoot, a rock that wasn't rendering was blocking your shots. Mobility was fukking AWFUL with all the hills and WW2 vehicles (Vanguard mode was the only way to play for a while too, which eliminated all the original guns and skins). There was so much foilage, visibility was a nightmare. The cherry on top was Krampus.
Oh yeah, they also went on holiday break right as they launched the map so it was at least a month before they fixed anything.
Rebirth has never been that satisfying to me, so I flat out stopped playing the game during this period. I would say it took them at least five months to get Caldera in a respectable state. By the end of the initial year, it was really fun. The POIs mostly being on the edges of the map will always be a terrible design choice but they made so many QoL improvements over its lifespan...and they didn't carry any of them over to WZ2.
If what Caldera is right now was released last year, the map wouldn't receive nearly as much hate and the mass exodus to Rebirth wouldn't have happened at nearly the same scale.
To me, Warzone 2 is like SOCOM 2 ---> SOCOM 3 or GTA: San Andreas ---> GTAIV. I remember when SOCOM 3 dropped, everybody jumped back on SOCOM 2 within a month and it basically killed the SOCOM franchise because they went away from what made it popular.
GTAIV was an insanely polarizing game that went away from the arcade style to realistic, especially with those WOAT vehicle controls. They did a 180 with GTAV after the backlash and payola reviews.
They knew WZ2 wasn't finished and the gameplay would turn off a lot of people from the original. They wouldn't have removed Rebirth and forced people onto this otherwise. That was such a tell.
Both games should have been kept up in full, including bringing back Verdansk to have a map rotation on the original. It's insane that they're killing support for that game already. CS:GO, Fortnite, Apex, Valorant, etc. are not burning down their core games or modes. With these being two completely different experiences, they should have left people a choice.
What's really wild is they released Fortune's Keep five months ago and already bushed it. What the fukk was the sense of even developing it?