These discussions are always a bit subjective IMO, but interesting.

If one assumes the user is experienced and practiced with the rifles.

A double rifle will always be faster than anything else with two shots.

A bolt action will will be slower for the first two shots, but probably faster for four shots. Assuming the rifle has a magazine of three or four cartridges. I think some of these new modern bolt actions with only two round magazines are a waste of time.

A single shot will always be the slowest.

Of course some individuals will be excellent with their chosen rifle, eg maybe faster than many even with a single shot. The same person would assumedly be faster with a double rifle and bolt action too if they put in the effort.

I assume the shots are all aimed shots.

Sometimes these debates are based on silly arguments. I remember years and years ago reading a supposed expert gun writer in a magazine claiming a bolt action was better than a double rifle for dangerous game. His "logic" - the double rifle will probably be chambered in a big bore calibre and have considerable recoil, so the recoil will affect its speed of firing, so a bolt action is better ??? Funny how his logic ignored the bolt action if comparable would also be chambered in a big bore calibre and also have similar recoil!!!

Some gun writers seem to lack pretty simple logical reasoning !