The big thing that should be in place by May 2023 is ETIAS, which is when the EU moves to an ESTA style entry process. In theory that means many more people can be processed by the e-gates. Recently LIS has increased the number of passport officers, but right now the impact is dented by the fact that over 5% of staff are currently down with COVID. That seems to be improving. They have also added the UK to an e-gate process, after Brexit UK citizens, one the largest visitor groups to Portugal, went from EU to the non EU passport controls and all movements need to be stamped. UK citizens now have an e-gate to take them out of the lines, though during peak periods the I don't think they were a big factor. UK to USA passage, or vice versa, would not usually require the passenger to be in the line. And no, it's not every day, it's not all day, there are quiet days away from school holidays and mid week. The bad days will get coverage here and elsewhere, the good days generally will not.