Yeah, that's not unusual, whether with a phone or GPS computer. I usually run both my phone and bike computer and it's not unusual for one or both to have a jittery, jagged trace some days. Seems to depend on weather, surroundings (there are a couple of segments along my usual route where GPS loses sync for a few hundred yards), moon phase and how much turmeric and essential oils Gaia sprinkled on the ozone layer.
Usually Strava does some smoothing. I usually record to Wahoo Fitness on my phone, then upload to Strava, and the data and GPS trace will differ slightly. Ditto, my bike computer's native app and Strava. My computer supposedly uses all or most global positioning systems (GPS, Glonass, Beidou) and switches automagically to whichever has the best signal, but there's no way for the user to determine that. I suspect it defaults to the primary system for our region.
Also, most phones can use cell tower data as a backup when GPS sync fails. I don't know whether there's any bike computer that can do that. This may explain the occasional significant variations I see between my phone and bike computer logs.
On good days when I get a solid locks and the GPS trace is smooth, I can see every segment where I change lanes, backtrack for a few yards to check out something interesting along the roadside and snap a photo, etc. Other days the GPS trace is so ragged it's very approximate. And it loses sync as soon as I step inside my apartment complex, so if I forget to end my ride/run before entering the building I have to use the crop feature to avoid nonsense data indicating I "rode" a mile of loops inside my building.