Not OP, but in Germany it is quite typical to receive a letter that officially states what were your duties and titles. Some employers expect you send them the previous job letters as a sort of background check.
It is also easy to read between the lines in the letter to see if you did just the minimum or they were really happy with you. The fear of a bad letter can keep people accountable until they leave (best case) or be used as a threat by an unscrupulous employer (worst case).
This affects international jobs a bit less, in my experience.
That is slowly changing so. First because most employers are afraid of legal disputes and give roughly a 2 (based on the German grading system with 1 being the best 6 being the worst). The de-facto legal minimum, without hard reasons to deviate, is a 3.
The second reason, nobody is asking for those anymore it seems. The last couple of jobs I took, nobody asked for any of my letters.
Otherwise I agree, it takes some internal convincing to not care about them if your are used to them your whole life.
Im short, those letters suck. And almost everybody knows it.
It is also easy to read between the lines in the letter to see if you did just the minimum or they were really happy with you. The fear of a bad letter can keep people accountable until they leave (best case) or be used as a threat by an unscrupulous employer (worst case).
This affects international jobs a bit less, in my experience.