Pliers in the rafter roof: removal possible and safe?

he meant they were only connected like that back then so they wouldn’t slip during the roof construction…

Could be, doesn’t have to be. It’s unfortunate that some craftsmen just blurt things out like that without looking into it more closely or checking it reliably.

Please do not imitate what @Ugarlino writes there and especially not what he shows with the picture. Such a nail plate does not have so many holes for no reason.

You mean: not so that one can play "6 out of 49", "Bingo" or "Connect Four" with it?

Three nails for two rafters. Cute.

Not much more fits with the distance between the beams. But clamps are not always necessary, it depends on the ring beam. Here it also looks like there are additional beams lying on the gable? Do you know how the ring beam is constructed? If it might even be made of concrete then the roofer could be right. Don’t give up but have it checked.

But clamps are not always necessary,

Carpentry is a master craftsman's trade and also includes the right to submit plans. I consider clamps without structural necessity to be a rumor.

it depends on the ring beam.

The ring beam would not stop the collapsing roof truss either; its responsibility lies in preventing the eaves from being blown off (which would be the next step after the house collapses).

Please do not imitate what writes there and especially not what he shows with the picture. . Such a nail plate does not have that many holes just for fun.

So the plate was attached like that on both sides and also nailed even better. Unfortunately, I just didn't have another photo anymore

The answer is quite simple, no you are not allowed to remove the clamps. A rafter roof is a system with foot points with horizontal and vertical supports with a ridge point as a hinge, e.g. as a lap joint or as in your case with a floating ridge purlin and the double clamps. Can you change it, yes, if you convert your rafter roof into a load-bearing purlin roof, which means purlins with supports arranged underneath. More or less sensible, as the purlins in terms of cross-sections will not be sufficient for the existing support spans, and you additionally need supports especially under the ridge purlin, which often get in the way and cause disturbance. Everything is possible but also very costly. But without an appropriate structural engineer, you won’t get by in this case.