I personally dont care if they were to offer real time with pause but its not how the game is meant to be played there are dnd games that do adapt real time with pause and real time play period but there choice to make a turn based game focus is good you cant say it all you want that real time would be good but factually it doesnt play to the core concept of the game being accurate to dnd which was announced months prior to the release. So if you think real time with pause allows that your you really have no concept of the design concept of the game which was stated well before you considered getting it like early 2020 it was stated the game would be an attempt to accurately carry 5e rule to the game which is the entire reason why some people purchased the game. Turn based saying there are lots of turn based games is very inaccurate unless your talking classic RPG's like FF7 in its original version and card games there hasnt been alot of options for people who want to use multiple characters in games since Xcom as a franchise. The 2 most recient games to adapt turn based play outside the current series with Solasta and BG3 both of which released with same concept of adapting 5e rules were Necromunda and Pheonix Point. Both of which lack alot of depth. Nercomunda is no really and RPG its more turn based stratagy and had a horrible initial release.
There are dozens of options to Real time with pause. King Maker was originally only released using real time with pause which was IMO horrible. But hey there are people who still prefer it because they don't like waiting on animations. Which hey if thats your thing thats your thing but a game that is designed to play based on a table top game using turn based combat is never going to be as tactical if you take away turn based combat or as clean and if your telling me you can perform a fight as cleanly with real time as any turn based player id be happy to put that to the test any day of the week. Its physically impossible to perform your turns as cleanly using real time as turn based as you are not 4 players controlling 4 characters. Nor do you have time to think out and play your turns as smoothly as a turn based style. If you want it purely to save time a better way of designing it would be to add an option to skip enemy play where all there actions just happen off screen so you do not have to watch it but at that point your losing key information in how to respond to there actions.
5e Reactions are a key part of the game play and using your reactions is very valid. For example the shield master feat being used to defend a nearby ally vs using your reaction to attack can be a key turn incentive to play. Positioning characters in 4 differnet locations to make your self harder to hit with aoe ect. Real time with pause this cannot be achieved accurately. Even if your apm is super high as a human being you physically cant react as 4 different people. However having real time with pause would be prefectly reasonable if you were playing a multiplayer game with 3 other people however then your taking all pausing on each other so that they have to wait for your turn and the same concept exists.
There are great games that do use real time with pause at the same time like the total war series and dragon age and the more recient ff7 remake. However at the same time those games were designed with that in mind even pathfinder wasnt horrible for people doing it because of the concept behind it however pathfinder it was still proven that turn based play was much cleaner than real time with pause because the core abilitys of the game are designed for turn based play and if your adapting a turn based game to real time with pause it will never be as clean as playing it turn based its just factual unless your purely controlling 1 character its physically impossible to a player to react for 4 people cleanly.
Saying that they should toss 5e rules out the window you clearly didnt watch the promotional trailer for the game where they stated the game was designed to be an adaptation of 5e rule to the game. I think larion is doing a great job of that and wanting to stick to the turn based system as a focus is the best way for them to do that accurately not to say that adding a real time with pause option down the road for people who just want to play the game in efficiently is a bad idea but factually focusing on completely adjusting combat so you can do real time with pause would take away from that as its completely adjusting pathing mechanics. You also have to factor in taking multiple actions with multiple npcs would be much more resource intense than one action at a time that occurs during turn based combat as each npc is reaction to the reactions of another npc and or player. It also messes up sequencing orders of attacks and just does not adapt rules well. Which again before the game was ever released they stated the concept was to adapt 5e rules to pc.
The exception to this being ranger mechanics because they just dont convert well to a pc game. Though they could be adapted and I personally dont see an issue with it but ranger was even stated by wotc needs an overhaul and will probably get a complete overall in the future because the class is just inferior to all the other classes as it is.
3.5 Paladin barbarian and ranger were all inferior to fighter overall as classes. 5e paladin and barbarian were balanced out as melee classes to fighter. Ranger however still suffers being lack luster in comparison as level go up so them choosing to attempt to revamp that i see no issues with that. As they are still attempting to stick to the core rules of 5e.