Electricians

Fridgie here. Just got some manufacturer training on some equipment that uses R-290 (propane) as the refrigerant and one of the interesting things in that training is that this manufacturer requires the use of wago lever connectors for any repairs on that equipment. They specifically tell you not to use any wire nuts or crimp connectors.

Why would they specifically require wagos? As far as I was aware the main benefit of them was ease of use and that doesn't seem like it would make any difference as far as the manufacturer is concerned. I especially fail to see how they could be more safe and robust than crimp connections. Is there something I'm missing here?