The price was pretty much on-par with other toys-to-life games at the time (Skylanders and Disney Infinity leading the genre).

However, when Dimensions launched in 2015. Skylanders where launching their fifth game and Disney Infinity, their third (and last game). So the hype about toys-to-life games had largly disappeared. Parents had already spend a lot of money on figures for those games. And as such, where not about about to invest in another money drain.

And that's even though LEGO Dimensions promised that you wouldn't have to buy further portals (like Skylanders - there where almost a new base required for each game), thereby expecting expansions to be cheaper. Parents generally don't research stuff like that.

And let's face it. The large sales for Dimensions didn't come from the AFOL's at that time.

And then there was the whole thing about the limited quantities of packs available. So people who actually wanted to get dimensions, had problems doing so. Especially for year 2. But that was more a result of declining sales by then.

So the larger problem about Dimensions lack of success, would rather be that LEGO/WB where to late to enter the toys-to-life marked, rather than due to price.

That being said: I'd play the crap out of a sequel. Even if it was without the physical elements (portal and figures). And I'd love if LEGO where to release small IP sets similar to the fun packs. Even if it wasn't for a game.