I've heard someone say that the RPG genre is stagnating, and in some measure, this is true. Most RPGs follow the sword-and-sorcery formula: be the chosen one, save the world, gather loot, kill monsters, solve FedEx quests, level up. More cyberpunk/sci-fi RPGs are cropping up, but those are far and few in the between. If mingling with other genres is what it takes for RPGs to grow, then why not? Very few games, nowadays, can claim to adhere to a strict genre label anymore. More and more RTS games, thanks largely to Warcraft III, are cloning each other and shoehorning RPG elements in. Some RPGs present simplified gameplay (KotOR) in order to cater to a larger audience (FPS people, for instance). Sound marketing plan, and it's not terribly detrimental to the game's integrity as a whole.
Besides, being a "true RPG" or not doesn't always directly affect a game's fun factor. ToEE is as old-school a RPG as you get, but even without bugs, it'd still be a dungeon-crawling bore to me. Awful writing, non-existent story, combat that eventually becomes quite dull. Curiously enough, ToEE is really just a tactical game with RPG icing, IMO. (I believe it won the last year's Gamespy "Old school RPG" award.)