Upvote:5
Looks like I'm going to answer my own question (and I'm rather disappointed by the unexplained downvotes). It seems there's a pattern of carriers doing this to a disproportionate degree and ignoring advice from the Home Office on what checks are sufficient for entry into the UK. From here:
Carriers are not currently required to check an EU, EEA or Swiss citizenβs immigration status, or their entitlement to travel on a national identity card, when deciding whether to bring them to the UK. They only need to check that they have a valid passport or national identity card.
According to the above, my EU passport was sufficient for me to board that plane and that person clearly overstepped their remit in indirectly implying I have forged documents and/or no right to enter the UK.