Nope, the point is the feature gives you very little benefit if a cantrip can provide all the same benefits and then a whole lot more.
Why not start off factually, it doesn't provide all the same benefits.
Anyone can take magic initiate feat to get guidance, another cantrip, and a first level spell.
Anyone, including the fighter can take the feat (if optional feats are allowed in that game), this doesn't devalue the ability in any way, since they stack.
Remarkable athlete is therefor less than 1/3 as good as a feat.
The champion fighter would be be better if they received the guidance cantrip as opposed to RA.
Nope, because guidance doesn't do the same things and RA doesn't prevent using both.
You really don't need the stuff remarkable athlete applies to in combat.
Nobody "needs" anything in a D&D game, they want stuff.
... You definitely won't be using stealth in combat as a fighter.
So, I have to stop now? You have that power? High Dex fighters were darn good at that
Nor will you be using sleight of hand.
Hey, you aren't even my GM, what's going on here!?!
Maybe you will use acrobatics in combat?
Whew, thank you for letting me still do that I guess.
Remarkable Athlete is overwhelmingly used outside of combat.
How do you even know these facts, do you have any sources? Is it mandatory that we change our game to make this so?
And outside of combat, the drawbacks of guidance disappear.
Assuming there are no time constraints, or consequences of failure, and that the caster is re-casting it every single minute, then some of the drawbacks disappear. We are still left with a situation where guidance can be cast on the fighter to make them even awesome-er, or it can be cast on another PC which is obviously a big deal with checks ie; initiative.
Your comparison clearly shows a lack of understanding of the issue. You compare like features to determine if one is good or not.
Your comparison is apparently based on games being played in a very narrow way, and fails to see the larger picture.
The comparison with remarkable athlete to guidance is to show that a champion fighter would be better off if they had the ability to cast the guidance cantrip than they are with remarkable athlete. It's sad that the champions most useful feature could be entirely replaced by a single cantrip.
Except it really wouldn't be replaced. Even in the tiny box you have constructed the cantrip is still nearly useless in combat, doesn't have the additional benefits of the feature, requires concentration, and has downsides. RA doesn't have downsides, it is an always on bonus. Unless by "entirely replaced" you mean "swapped out for something different", it seems
Note, I'm not saying remarkable athlete isn't a half decent feature, it's just not some wellspring of amazing utility only available to champion fighters.
Here we certainly agree! I would describe it as "shoring up" rather than any sort of wellspring. It makes the fighter just all around "good" at physical skills, even if they chose a non-typical one at chargen. It helps them cover their bases and have a good chance of doing most "athletic" things.
Anyone who says remarkable athlete is amazing is plain kidding themselves at the value of its overall utility.
Or, perhaps playing the game quite differently than you are? Things like whether or not players regularly attempt improvised actions in combat, whether or not things are happening in combat other than fighting, whether or not the GM uses many skills with alternate ability scores, etc. etc. might have a big effect on how useful RA is (and most of which Guidance is almost useless for).
I am guessing your answer will be "No, people playing that way are doing it wrong, they should play in a way that makes this ability useless, like I do."