This is unusual for U.K. families who are really settled, so it isn't surprising that most can't imagine doing it here.
Personally I have never done 5 weeks, but both me and my partner have been away from my son for 2-3 weeks at various points. We are an international family split between far away places, and with work it isn't always possible for everyone to travel together. Last year I had an elderly relative with a medical emergency. My work would let me have time off, but my partner's wouldn't.. so I went back with my son (4 at the time) alone. Equally, my partner has taken my son back to their home twice without me, because I had to work, and they both had time free. We were also split up when moving cities a few years back.
As long as you have two parents, who are both loving, capable, and responsible. Having one of them be away temporarily won't matter. I would only worry about it if the remaining parent isn't capable.
For us, we found video calls helped, but with specific things to do. Not just "chats" because kids often struggle with that. Last time we were apart, I called my son every night and did his bed time stories by video-call. I downloaded some E-books, so he could see the pictures on the screen while I read them. It became our routine for 2 weeks, and was much more effective than just hoping he would leave toys/playing to sit and talk to a camera.