I just took a quick read through the article that you posted and it seems that he gets sued by a single dogecoin investor. So for me this means that it is pretty safe to say, that this legal action has zero chance of being successful, especially when you look at the amount that this guy wants as a compensation. I think the guy who sues Elon Musk definitely knows that but still sued him to make a statement or to make this issue more public again.
In the end the Dogecoin shilling of Elon Musk was very good for those guys that were already invested into dogecoin before the shilling happened, but also very bad for those that only bought Dogecoin because of the shilling of Elon Musk. I mean in the end it is also the fault of those guys that just buy a coin because someone famous is making tweets about it.
I also think that the shilling of Elon was bad for the crypto market as a whole because it was basically the starting point of the meme-coin hype and because of that we saw hundreds of new shit-coins every day and attention was took away from real projects.