I have not tried it myself (and do not intend to, for multiple reasons), but I have seen people down 300+ ml alcopop bottles in much less than six second. The neck of the bottle would be about the same or slightly thinner than the one ounce vial in @Horwath
's image, and the volume is an order of magnitude more.
I mean if we want to go down this rabbit hole, let’s get into the absurdity of bottle durability. The bottles are almost certainly glass, as most games don’t have plastic.
These bottles are on the bodies of adventurers that:
1) dive to the ground to avoid fireballs. (Or get hit with said fireball)
2) get ripped up by giant beasts.
3) are thrown like rag dolls by giant scorpions.
4) are pulled underwater by giant whirlpools
Etc etc. yet those little glass bottles survive all of it. Now THATS absurdity.
When it comes to potions, we simply accept a certain amount of insanity in the interest of clean gameplay. My players have never batted an eye that bonus action potion drinking was the straw that broke the camels back…it’s just added to the pool of absurd things they already accept around equipment