I mean it's literally a few minutes on a charger to go from 5% battery to 60%. Would it be more convenient if it went longer? Sure, but as it stands, if you carry a watch charger in your bag, like... even the most minuscule time on a USB port will have it ready to roll.
I've got an SE at current (had a 4 before it finally keeled over, and this one has essentially identical features and was readily available) and I just don't get the battery griping. Mine only uses a scant 70% ish of it's available capacity. I wear it every day while sleeping and to/from work, then come home and toss it on the charger till bed time.
I have a handful of watch chargers including one at my desk and one in my laptop bag. A full day of kid activities and work around the house doesn't really see either of those though. Do I detour to top up the watch a couple times a day? Yes. Does my watch run out of juice some days? Also yes. Would a Fitbit or Garmin have this problem? No. It's a bit of a slog moving my health data out of Apple's ecosystem which is why I haven't done it yet.
I've got an SE at current (had a 4 before it finally keeled over, and this one has essentially identical features and was readily available) and I just don't get the battery griping. Mine only uses a scant 70% ish of it's available capacity. I wear it every day while sleeping and to/from work, then come home and toss it on the charger till bed time.