I never played the first game, heard it was pretty bad from the people I know that had played it, so didn't bother buying it to see either...
It certainly wasn't bad. Neither was it amazing. Got an 81 meta from critics. It had some issues, the storytelling wasn't great, the driving portion felt pointless, and the game ended abruptly, making people feel like they payed for half a game instead of a full game, even though it actually took like 20+ hours to beat the game if you did all the side stuff. However, the things it was good at, it truly excelled at. It had excellent shooting mechanics, the best enemy AI in an FPS to date (yeah, imo the AI in Rage has still not been surpassed by FPS devs 8 years later), and fun weapons like the wingstick, a bladed boomerang that tracked enemies and was kind of OP.
It was certainly a good enough game to warrant a sequel, id has improved since Rage 1 released, Doom 2016 reviewed 4 points higher at 85 and got a GOTY nomination at the 2016 Game Awards and won Best Action game there. I trust they can remedy the issues with the first Rage and make Rage 2 the game they wanted Rage 1 to be.