Not having seen
MOS yet, I shall delay my review of Cavill’s performance.
But some general thoughts… My idea of a properly realized cinematic Superman is the “Gary Cooper” type - strong and silent, calm and confident, reserved and often enigmatic. In other words, it’s not the kind of role that (imo) readily lends itself to a dynamic, histrionic, Oscar bait sort of performance.
Christopher Reeve gets deserved praise for his work in
STM. But in large part, this was because the role (as written) offered a showcase for his thespian
range - stalwart and serious (for the stereotypical Superman lines); warm and cutesy (while rescuing kittens or flirting with Lois); comically buffoonish as Clark Kent. Reeve’s talent isn’t at issue. But it might be argued that his virtuoso efforts were not, actually, in the best service of the character. Certainly, some have complained that his CK was a bit over-the-top, that CK shouldn’t be comic relief. And in retrospect, the puppy-love scenes with Lois come across as a tad too forced and saccharine. Now if Reeve/Donner had dialed some of this back, I think they would have gotten a truer depiction of Supes/CK. But of course, Reeve probably wouldn’t have received as many accolades for a more subdued and constrained performance. So I think it comes down to what you’re rooting for: the actor (his awards, reputation and future career) or doing right by the character and story.
If Cavill ends up being wooden and bland, I won’t hesitate to say so. But I’m not expecting (nor do I want) Daniel Day-Lewis-style soliloquies or Tony Stark-esque wise-cracks. I want “Gary Cooper” as Superman. I think - hope - Cavill can handle
that much.