Arthur Clarke observed that humans are over optimstic in the short run (flying cars, etc,) and under optimistic in the long run. No one seeing a Model T when it first came off the line would have imagined living long enough to see people walking on the moon.
We will travel to the stars but I’ll be long gone to dust by then. But we’ll be there.
I’m a long term yes but that’s discounting great leaps in technology which are also possible.
There is a lot of promising research going on as well. The VASIMR engine is logging a lot of working test hours. There is a solar sail in production with plans to launch in a few years. The Orion project is technically possible but expensive and the political implications of launching thousands of nuclear bombs into is obvious. Even the Alcubierre warp is being tested with what scientists are calling promising results (currently warping space by nanometers)