They changed developers when they went to Nitro and Thunder. That was their first mistake.
Maybe if you're not a wrestling fan or got into them late. The latest games by WWE has fallen into the wash, rinse, repeat that a lot of games today do and the industry is less popular than it was in the late nineties. But there were some decent games back when wrestling was still hot to choose from, many of which were made by the same developers. War Zone is praised pretty highly too since it introduced 'Create a Wrestler' and had a lot of good options to choose from that would carry over to the rest of their games. Then there was the introduction of season mode.
tl;dr: Nitro and Thunder set the standard of the trite that none of the others have been able to surpass since their conception.