modern admirals are fraudulent toptiers
they have nothing which symbolises what a toptier should be
merely changing the climate of the island aint impressive when ace can do an inferior version of that just by existing
the only thing in canon which portrays the gateway to the toptier realm is skyspitting
or some other insane portrayal which shows u going toe to toe with these skysplitter like oden
tho i think oden might as well be capable to do a skyplit himself , we just didnt see him clash with another proper toptier
now comes the admirals of modern era , they barely have any portrayal which puts them on the level of sky splitting
the main thing is that they dont even have conquerors haki , so they simply dont have the potential to get to that level
the only marines portrayed to be skysplitting level are garp and sengoku in old gen
both of them are also confirmed to possess conquerors haki
with garp directly showing advanced conquerors
these sky splitters are on a different tier
u can easily see that in their interaction with admirals
lets start with old people ( characters with the portrayal of being skysplitters )
1. here is oldbeard defeating the strongest admiral
2. here is rusty rayleigh stalling an admiral
3. here is garp actually beating an admiral in every interaction
imagine what will they do in their prime
u also have instances where shanks simply Wi-Fi diffs greenbul
or luffy beating kizaru the moment he uses acoc
there are levels between them
well end of the day , the term ' toptier ' is not a canon term in the manga
thats why there are lists of low TT , mid TT , high TT
i consider admirals in the mid TT range while the true toptier range starts from high TT ( sky splitters )
high TT is also where prime garp and sengoku should be