Yeah absolutely, imagine when military budget and NASA budget were swapped. I bet we were already colonizing Mars and probably other planets as well.

"HEY! OVER HERE! YEAH, THAT'S RIGHT, HERE!!!"

Well actually they make things about as good or better than they used to. Remember that mars helicopter that was only supposed to last a few flights?

If anything, they are building them better. Their rovers now vastly exceed their original missions. Satellites now form an interplanetary internet network. We even have a helicopter on Mars! It's reached the point where it's playing spotter for the river, since they've run out of experiments to run on it!

There was 1 (experimental) mission into using ion drives. Multiple drives failed. 1 only lost its +ve ion thruster, another only it's -ve thruster. They managed to reconfigure it in flight. The 2 drives were interconnected via an FPGA processor on board. They rerouted the engines through the computer!

Don't get me wrong, Voyager I and II are amazing. However, given the same opportunity and funding now, the result would blow them away in almost every department, including longevity.