FPS is the game engine speed, what you thinking is the speed of the character that is not related to the engine of the speed. This is why you think the character is able to do something impossable. I can test many engines with 1x1 pixel block and the speed of said character will not matter because the hitbox stops it everytime. Only when the engine is poorly made is the reason for character to pass through the 1x1 pixel.
Delta timing is not to be used on all games, frames is also commonly used as this engine runs only in frames: https://firecat.itch.io/arcade-game-studio the engine does not make the character slow or faster. Delta timing is just a check based timing event and it has nothing to do with speed of the character.
As i said collision will always stop character/object, the engine only effects the world and it's rules. The clipping has been proven fact of many years of bad angle and size of the hitbox. There is nothing about the character being able to by pass a collision without seeing a mistake in the code.
I suggest you learn more about programing than relaying on engines and plugins, what you see vs what is coded is very different.