DRS is a invention for people who love to see overtakes but not battles.
IMO the boring races in the 00's were caused by too durable tyres. Overtaking was possible. The problem was that the fast cars were always in front. They never suffered too much degradation or anything like that. Once the fast cars started from behind they proved that it is possible to overtake. Kimi Suzuka 2005
With the soft Pirellis we got good action. Sadly and thanks to DRS, the battles are over after one DRS zone.
I'd really like to see a race with those soft tyres but without DRS.
I think it's not so simple. DRS makes passes between cars with preexisting speed differentials very easy. However, for cars of similar pace, it makes overtaking possible, and leaving aside a few bad implementations, defending is also possible.
So in this case, you're right. DRS would have made Trulli a sitting duck. But let's look at some more recent examples. Alonso vs Vettel in Silverstone last year. IMO this would have just been two cars following each other around until pit stops without DRS. Same for Hamilton vs Rosberg in Bahrain. So basically, I think that it's made passes on cars out of position too easy, but I'm OK with it because of the trade off on which cars of similar speed can Duke it out.
Was there ever any doubt Schumacher would get past Trulli? No. It's still a great dog fight, but if that's the only passing, it's not going so well.