You're just naming the most basic elementary things, kids know that about bears. Doesnt mean kids can prove those attributes beats the King of killers:
LION, King of Killers (October 4, 1914)
The bear had all those advantages over pumas, yet that didnt stop a only 150 lb big cat from killing 1,000 pound bears. What does the bear have that the lion hasnt already dealt with? He has a bite...lions kill crocs who have the most powerful bite, he has size, hippos are 3x bigger...he has claws, so do leopards, tigers and atlas bears, he has stamina, so does buffalo. He has protective fat, crocs, rhinos and elephants hides are just as if not more durable than bears. Theres nothing the bear has the lion hasnt already faced with of a larger or more powerful form.
So it will come down to either showing...
1.) Actual bears killing lions
2.) Or feats of their prowess
Bears have only killed lions around 5 times or so, lions have 30+, and lions have killed polar bears more than any other bear in captivity, so how can your elemntary argument of bigger = win, be taken into account when polar bears > brown bears. How about some feats of bears...theres barely even ten genuine records, humanity has been documenting these animals for thousands of years, and yet you cant even find 10 formidable animals brown bears have killed with root documentation? lol that just shows the bear is not as combative as you think him to be.
While theres nothing hidden, or secret, or misrepresented about the lions title, power and attributes, lions can actually back up there status as King of beast:
One of the greatest lion tamers of all time: Clyde beatty
The Lion might not be GOAT, but the lion sure can kick some ass.