It is definitely going to be extremely difficult to replicate what was achieved in the last decade, and I do agree that the slate is based on a 3rd tier of characters, as opposed to a 2nd-tier for the Infinity Saga, because 1st-tier was already licensed out.
But ...
The Infinity Saga was only a throwaway plot and teaser in the Avengers, fully at the end of Phase1 of the initial movies. Even the Tesseract was seemingly setup initially telegraphed as a modern take on the Cosmic Cube, rather than an Infinity Stone. So if you want to compare, you can only judge at the end of 2021, having seen the initial 2 years of build-up, character establishing movies.
And ...
RDJ was in obscurity when cast as Iron Man, most general movie-goers had forgotten he existed. Chris Evans was not a household name, and Hemsworth was virtually an unknown. So again if you remember where everything sat when the MCU began, sitting now on judgement on films and plot lines and any over-reaching arc, nobody knows much of anything about, and already believing it to be automatically inferior is harsh.
I personally like the idea of the Galactus story being introduced as it is an iconic story for the FF and hasn’t been done. But I can’t help thinking the Kree/Skrull War, possibly combined with Secret Invasion for the Earth-based movies is where we are heading, based on recent movies, held together by combination of FF and Captain Marvel/Eternals/Guardians and New Avengers forming. I think X-Men will be held back until after all this.