@Background Pony #7C7A
In my mind they are somewhat distinct by the shapes of the fixtures and supporting hardware. These are just my mental imageries, not official use of terminology:
I envision “lamp”s to be round or faceted glass and mildly old-timey or a modern spin on the same design goals. I envision “posts” to be shorter, around one story tall, compared to poles, which might be more like 2 stories tall. And, a lightpost would be tall and have non-lanp-like fixtures, whether they’re modern downward-facing hemispherical lights or a grid of projecting lights as for a stadium. In a lightpole I still envision a more modern version yet still with light(s) on top of a shorter pole, without an overarching bar like a streetlight.
Of course, these impressions are not codified into tag definitions, at present.