Casual Interstellar Travel / Casual Interplanetary Travel: It’s a little complicated. Technically, yes, you can travel interstellarly fairly casually, since while you have to drag one end of your wormhole at subluminal speed to wherever you want it, interstellar travel to places where you have one already is pretty damn casual. Step through and you’re there. Ping.
Of course, wormholes and their associated stargates are Really Damn Expensive, and so is interstellar travel to anywhere that isn’t on the stargate networks involving as it does the many years relativity demands of you even in lighthugger starships, the great expense of said lighthugger, and for that matter, the even greater expense of the thousands or tens of thousands or even, for the largest luggers, hundreds of thousands of tons of antimatter you need to fuel the thing.
Further, and to subvert this slightly, while there’s casual interstellar travel, what there isn’t is casual interplanetary travel (speed-wise; it’s much more casual cost-wise). No-one’s invented a convenient magical gravity drive that lets you whip up nigh-instantaneous thousands of gravities of acceleration (while there are vector-control drives, neither acceleration nor delta-v are any better, and indeed usually worse, than equivalent reaction drives; blame conservation of mass-energy), so getting anywhere in-system, including out to the stargate, still takes days or weeks, and for interstellar travel, that means on both ends of the wormhole.
This is resubverted for those with the right metaphysical attitude, because if you don’t go into quivering neo-Luddite theofear at the thought of having your mind separated from your body and transmitted elsewhere to be reinstalled in a different one at the far end (and granted, that’s not exactly most people outside the rampaging postsophontist neophile civilizations), then you can just mindcast where you want to go (assuming of course they have the right receiving equipment, which is by no means guaranteed outside the aforementioned civilizations). Which is substantially quicker and counts as fully casual interplanetary/interstellar travel, because photons and (especially) tangle move a lot faster than your own personal meat/rock can be transported.