father_of_6
Membler
I've been using blue wirenuts on #6 AWG wire for 35 years. Not so much now, but my employees still do. If done right, they will work for ever.
I'm not electrician, but have done work on my own home. Having to cut back old Romex to twist new caps on is a hassle and sometimes not possible due to length and/or space constraints within existing junction boxes.
I'm not saying wire nuts are an invalid solution, just that for the purposes of my own home and the little bit of electrical work I do, the tiny increase in price of using WAGO connectors pales in comparison to the significant increase in convenience that they provide me. I have several boxes of wire nuts, but I ordered an assorted case of WAGOs and it's likely enough to last a lifetime... I just can't see myself ever wanting to use wire nuts again.