Yes. Even tossing out the "outlier" interpretations, there is plenty of room for metrical variation (e.g., whether the punctum is 120, 100, or 80), as well as how much to 'work' the accented syllable, how much to utilize diminuendo/crescendo/rallentando....

And then there's the French nasality, the German umlaut-everything, and English/American broad-vowel/head-tone preference.

Best advice I ever got: "Sing it as though it were music." You'd be surprised how many people don't get that.

Ralph has offered the single most important word in this discussion: 'rhetorical'. Chant is rhetoric! Its earliest notation evolved as an adaptation of the rhetorical markings of the Roman and Greek schools of rhetoric. Every text will have its own delivery, based upon the speech rhythm, the grammar, and the nature of the text, i.e., whether it is laudatory, reflective, prayerful, ecstatically joyful, retells a story or biblical incident, and so forth. It is as absurd to suggest that 'in chant the punctum is 120, 100, or 80', or any other. This is as laughable as suggesting that 'in classical music the crotchet is 120, etc'.

Whether one is singing in Latin or English the very first step is to read, speak, and inwardly digest the text and its ethos, to deliver it rhetorically. The music, then, will suggest itself in relation to this. Rather, the text will, then, suggest how the music may be put upon it as a well fitting garment graces the contours of its wearer's earthly frame.

Nor should one expect that all performances of a given chant are alike. This is healthy and fitting, just as fitting as that no two performances of Brahms' piano quintet will sound alike - heaven forbid! Imagination and 'educated interpretation' are as important in chant as in any other music.

Yes there is quite a lot of variation.
I guess you just have to find the one that is your preference.
Most people will understand solesmes style.
Many interpret semiology differently.
Some choose to argue about it.
I like what @Hugh does, I've sung I think 7 different ways to chant now and his makes a lot of sense to me. I believe dr. Mary berry is partly responsible also for this interpretation.

I guess the trick is to read lots about it and work out what you like if you're a director. Otherwise if you're like me stick to whatever you're doing with whoever you're with at the time. I had to adapt a fair bit at the colloquium as the chant was almost at half tempo is was slow. It was great for vespers because it meant I could say all the words. There also wasn't pulsed notes when two of the same neume were in a row so I had a bit of adjustment there too. When I direct chant I think I try to find a speed that flows like the one I am most familiar with but when chanting simple tones I prefer slower to avoid rushing.
In different acoustics I'd also do something different.

I recommend checking out the triplex.

Depends on how you aspirate, Andrea. ;)