I’ve also had a lot of lucid dreams since a young age. Nearly all before I even knew what they were and from what perspective they were supposed to be viewed. They have always been in 1st person as though it’s me actually there.
Though there is no reason why that should be the case, after all anything is possible in a dream.

My offered explanation is perhaps your not always very lucid and so your mind is more open to the impossible. (or maybe playing too many computer games jk)

EDIT- perhaps after knowing more about lucid dreams, the next time it happens you may be in 1st person, or if not you may find the ability to convince yourself change it.