Oh go on then, I'll bite.
You've proven my point though. Those are the only examples you can think of because there's not that many of them - most levels on SM64, in order to be completed, have to be selected beforehand. There's no freedom of order like in Banjo - you don't just load the level up and complete objectives as you come across them, a la B-K. You select the world (which is the backdrop to your objective), load a specific scenario and upon completion, the game spits you back out of that world, ready to choose another scenario. Now there are times in Mario 64 - that you've listed - where the scenario that loads also allows for completion of another scenario. The result is the same, though: get the star and the game spits you back out of the painting.
You're stating this as a strength to SM64 over its sequels, because the fact that some of these scenarios allow for different outcomes is apparently an example of a greater 'freedom'. That's not the case! For starters, these situations are exceptions, not the norm - Mario 64 is not as free as Banjo-Kazooie. The order in which you complete the objectives may be branching and up to the player, but the objectives themselves are still linear.
Secondly, how is this a strength when it's clearly evidence that the game is simply re-using the exact same environments but with multiple star locations? Viewed dispassionately, it's a bit of a cheap mechanic. Using the examples you gave: when you load up
Snowman's Lost His Head, you're not playing a new level. You're re-playing the same level you beat twice before when you played
Slip Slidin' Away and
Lil' Penguin Lost.
Nintendo knew this was cheap - they did it to get the game out on time! They didn't do this with Sunshine, with far more of the levels unique and tailored to the scenario. There were still the open-ended objectives that could be done on any level/scenario, though, like the 100-coin challenge; and the Delfino Plaza Shines could be found in a branching order. Sunshine's a smaller game than SM64 - Nintendo knew this, but their padding was different. They introduced Blue Coins, and instead of having the same level advertised multiple times as different Stars, they instead presented them as hidden stars. This would carry through to the Galaxy games, where AFAIK every single level is unique but some have a main star and one or more hidden stars. Plus each world only has a few scenarios, but there's loads more worlds. It's far more inventive - one of the reasons I think it's the stronger game(s) than SM64.
So if your argument is, Super Mario 64 re-uses the same exact levels multiple times, more often than Sunshine does, then I concede that you are correct. There are more situations in Mario 64 where you can enter a world and get multiple stars from that starting point, than there are in Sunshine - you are right. But there aren't many. And that's a good thing, because what you're referring to as freedom
isn't.They're extremely similar games that follow the same format. 64 is set in a big castle with lots of small rooms and corridors, Sunshine in a medium-sized town with some smaller areas off it. 64 has more worlds with fewer stars (some of which can be obtained in identical scenarios), Sunshine has fewer worlds with more shines and probably, on balance, the same number of unique scenarios as SM64 when you take into account hidden shines and blue coins.
I think what you're asking for is a return to the Banjo-formula, but that's not really what SM64 ever was. The levels you allude to as somehow more sandbox than others were only ever so as an attempt to lengthen the game without creating new content. I would rather see more unique environments and fewer re-uses - a template that the Galaxy games followed to its extreme, with fantastic results. But completely going in the other direction, a la Banjo, and having massive environments with multiple collectibles, could also work. So long as the game doesn't reset you every time you complete just one objective - as no matter how you put it, that isn't freedom.
Therefore, having considered all of that:
"Super Mario 64 gives you significantly more freedom over the order in which you can get the stars than Super Mario Sunshine."
I disagree.
They're all cracking games though.