Time dilation and space contraction only matter if you can reasonably achieve speeds of a significant portion of the speed of light. AFAIK nobody has even come up with a reasonable way to achieve this for lightweight probes, let alone for hundred-ton ships capable of carrying humans. And let's not forget the practical problems like all photons incoming from the front being blueshifted into ultrahard radiation that would make a point blank nuclear bomb seem like a small candle.

Realistically even getting to the nearest star in less than 400 years experienced time is way way WAY out of reach for now.

>but if it's just about you, the speed of light is no limitation at all

It's a huge limitation, even just getting propelled to "big enough speed", say 1/10 the speed of light.

We barely do 1/1500 the speed of light, in unmanned probes, and only because we sling shot on Solar gravity, not as propulsion or anything, and at 1400 o Celcius, plus deadly radiation, not to mention any micro-meteor as big as a particle of dust could kill someone there).

Don't even need to do time dilatation - just make you lifetime longer by techjlnical means (ideally almost infinite) and you will be in the next star sumystem before you figure out how to exit your VIM session.

> Time dilation and space contraction mean that you can get there in as little time as you desire.

This is confusing science fiction with physical reality. See e.g. https://math.ucr.edu/home/baez/physics/Relativity/SR/Rocket/... for a reality check.