We don't talk about Pun-Pun
The GM always does have the final say, but when dealing with a spell that says "use a spell slot and this (exact effect) occurs", most GM's will default to letting it work (unless the player is trying to do something outlandish)...in my experience.I've never seen a situation where the player had any more control over spells than skills in person or streaming. The DM always has final say on what a spell does or does not do. About the only gray area is around illusions, but the adjudication is similar to skills.
Further, when attempting to make a skill check or checks to perform a task, it's also been my experience that GM's are very conservative about the the time required, whether multiple checks are required, etc.., assuming the task can be done at all. And the main benefit of spells is the time required is listed in the spell description.
It can take considerable time to set up a camp, as an example, especially at night, or in adverse conditions. Ability checks might be involved. OTOH, Tiny Hut can take as little as 1 minute (if using a spell slot) or 10 if used as a ritual. A GM could, of course, say that uninterrupted casting for that length of time is made more difficult, but the base time frame is set, without having to look up on line or draw on personal experience from camping on how long this should take.