That isn’t done without reason usually.
Fortunately, since I have never encountered this situation throughout my immigrant experience (GC to Citizen) even though I was at one point traveling every week I cannot speak for others.
Very disheartening to hear about that traveller's terrible experience. I should have hoped that the normal experience of a traveller, even today, would have been such as yours.
I have been detained thrice at immigration/entry control in over 500,000 miles of air travel.
Once, at Franz Liszt {Liszt Ferenc) Airport at Budapest, where the young immigration guard stared for many minutes at my visa with seeming incomprehension, before finally giving up trying to bore a hole through the page with his intense stare, and waved me in.
The second time, at Kuala Lumpur Airport, an identical incident happened; nothing wrong with my visa (here, too, there was not more than a glance at the rest of the passport document, that was stapled to my two earlier booklets, and contained a plethora of visas), and after nearly fifteen agonising minutes, I was passed in by an obviously sceptical but helpless officer.
The third time, at Kuwait, my visa stamp and passport number (on a separate piece of paper, not my passport page) clashed, and the numbers could not be read clearly. This time, it took nearly half an hour in segregation before they were satisfied about the bona fides.
These procedures have become increasingly difficult with every passing year. In 1986, it was possible for my wife to very kindly inform the immigration officer at Heath Row that she was not travelling alone, and pointed me out, twenty paces further away, still in queue, as her travelling companion, describing me as the bearded fellow who looked like a terrorist. Today, we should both have been put in strict detention while they satisfied themselves about our antecedents. Then, it only got a snigger from the wretch, and a wave of the hand for me to step up and get both passports stamped.
So you basically pulled a "Karen"...well look what that got you.
Hah!
Reddit junkie.
Trust me when I traveled to India and Bangladesh, at times, they made my life hell.
LOL.
No problems, all throughout, either India, returning from business travel, or in Bangladesh. In India, I aroused the contempt of Customs officials both at Delhi and at Mumbai, when I tried to pay for my excess liquor carriage (a bottle over the limit); they just weren't interested, and asked me to move on and let them focus on the big fish! Same thing, less drama at Bengaluru and Chennai and Kolkata.