Literally stealing my ideas m8
There are two issues with this idea though: First off, the DayZ engine uses a lot of Arma III's code (for some reason), and also contains code from the RV engine that is hasn't been deprecated in Arma III. This is bad because they don't want to open source some of the proprietary code they are still using for their main game.
Also, we all know that modders will give up on the wreck that is DayZ's engine and backport (forwardport since DayZ's engine is older than Arma III's even though it's a newer game?) DayZ's most interesting bits (Chernarus +, some of the items, etc.) into Arma III, leaving the original game a ghost town.
In all, this is never going to happen because people still seem to be buying it and they only have to put minimal effort into maintaining it.
Anyone who can't see that Standalone is killing the server more than anything else is kinda blind or being purposely misleading.
First, why not use the renderer and engine of Arma III? The map files are almost 100% comparable with one another, and if their version of RV is just a modified version of Arma II's engine with several of III's enhancements, it should be easier to port over or recreate the systems of Standalone than fix their mess of an engine (but its too late now anyways). Instead, we have a half-baked frankenengine that has awful ballistics simulation, terrible performance, and several bugs that honestly shouldn't be there. Why? I have two answers.
First, there is a (strong) possibility that the current development team is either incompetent or are lead by someone who has no idea what they are doing. Personally, I would bet it's both. Dean left super early on for unexplained reasons, and they might put new devs on DayZ while their main talent work on Arma III. This is very common in game dev (ask me how I know).
Second, there is the more malicious answer that Bohemia might be purposely skimping development resources on DayZ because they have no financial motivation to continue development. There are over three million owners of DayZ according to SteamSpy, and the game has about 3.5k players consistently. Arma III has a very similar amount of owners, and has about 28k players going all the way to 35k. Plus, Arma III is a released game and sells DLC *on top* of the base game.
DayZ did *not* cost very much to make, and they are not actively developing it. Sales of DayZ are slowing down as most of their target audience by now either owns the game or isn't likely to buy it. Arma III is the same way, but is supplemented by DLC sales like Apex. DayZ has no DLC and most likely will not add it to avoid community backlash, killing all sales they might get on sales and uninformed users. Therefore, we have what I will call the "Star Citizen Effect". Since the consumerbase already owns the game, there isn't a financial reward for actually releasing it. DayZ is no Star Citizen, as they do not have a payment model like Ships to supplement development (love it or hate it, I don't care), meaning BI has no reason to ever work on the game to the point of a release because they already have your money. Several Early Access games fall into this trap, and can't support themselves through development as they cannot continuously generate funds and traditional investors know that.Therefore, there is no priority to develop DayZ as they have no real way of monetization before or post release.
Therefore, DayZ will not be released as promised or at all as the money has already dried up. Am i calling it a scam? Not really, you and I knew the risks before we bought it. At the end of the day, blame capitalism or predatory early access sales gimmicks.
Also, don't go into gamedev kids, it pays like shit.
Edit: in the process of typing this rant I accidentally missed the main point: Your server is dying because people who own the game are either banned or have stopped playing, and there just isn't a large influx of players to join because they have no reason to buy the game in it's current state and this state will never change.
Also, here is that steamspy data