Here is how I look at it. If I am currently playing WoW and plan on playing the new expansion as well then I pre-order the game every time (Collectors Edition and before digital copy too since they didn’t used to send digital keys when it shipped). I have 0 reason to not pre-order it. I have enjoyed all the expansions except I hated Cata once that was all said and done.
People today are wayyyy to judgy on everything. If I was like those people, I would barely have any movies I enjoy, food I eat, games I play, etc. For example, I loved BfA. People can hate on it all they want. Their OPINIONS about that expansion are not facts and not law in the sense if they hate it then therefore it IS a horrible expansion no matter what and if you think otherwise then something is wrong with you because their likes are the almighty.
SLs isn’t in my tops for fav expansions but I still enjoyed it and I KNOW I will enjoy the next expansion too. If I ever get tired of WoW then I will just move on and not pre-order anymore. However, I have been here since day 1 of Vanilla launch and have yet to take a break. I may have taken a couple raiding breaks after finishing normal but still would log on at times and still play at least a few times a week.