It depends on what you are looking for from a football video game. If all you are looking for is a fun arcade style game to have fun with for a fifteen minutes or so than indeed TSB would be hard to beat. However there is a lot more strategy and depth to the games these days then there was when TSB came out and if you enjoy that strategy and depth than the current Madden games would probably be preferred.
TSB was revolutionary at the time because it was the first game that you could play a full season schedule with that kept track of your stats. However it was also an extremely simplistic season. Basically unless a key injury occurred you could count on the same exact teams going deep into the playoffs and the players would have virtually the same kind of stats every season you played. Virtually it was the 49ers, Giants, and Bears in the NFC and the Bills, Oilers, and Dolphins in the AFC. Basically 95% of the time you could count on one of those combinations to be the Super Bowl matchup. And then the season ends and you start the 1991 schedule up all over again to virtually the same results.
These days not only is there a lot of depth in terms of gameplay (the amount of strategy the people that play Madden competitively use is mind blowing for a video game) but there also is a lot more depth in terms of options and career modes. You can do an entire career where your teams will change from year to year. New players will be drafted into the game, players retire, and players age from year to year with their ratings changing.....etc....etc....
So again it just depends on what you are looking for from your gaming experience. The games these days resemble real life football a lot more closely than TSB does.