That's totally the opposite to how you should look at it!

The daily goal is just that - you are supposed to hit it every day (or at least be able to come close), just like the 30 minutes is your minimum.

Otherwise - how do you keep track of whether you burn enough every day? Sure it's nice to have something aspirational, to struggle for occasionally, and appreciate the victory - but that's what 200, 300, and 400 are for! By your standards, 400 should be virtually impossible. And you just ignore the messages motivating you to meet them, while to me they're actually relevant, useful, and effective. The whole point of the streak model is to ensure you do hit your basic daily minimum! Not give up 9 times out of 10 and say "fuck it, goals are for rare occasions". Health is for daily goals, ya eejit! I can't stress this enough.

On many days I have to slot in an extra 10-15 minutes to achieve my goal, but I've hit my goal for 90 days straight, had plenty of 200s and a few three hundreds in that time.

Probably a 400 or two, but they're rare and prized.

Wow, a record of consistent performance set accurately at an appropriate level, plus a variety of levels of reward. Such logic. Apple designed that because that's the standard recommended medical model - stand every hour, get minimum 30 minutes of exercise, and - every day - burn a suitable number of calories for your personal situation.

You're not getting that recommended base-level monitoring benefit.

Remember that the Apple Watch ain't about being a challenge that's hard to beat - it's about ensuring that you do meet daily health goals. If you set it up so that it's difficult to meet your daily goals, you're doing it wrong - ask your doctor.