BA lounges operate as status and not as a service. My own experience traveling with my elderly father illustrates it perfectly. We were in Concorde Room in T4 (few years back), flying F on BA. He is in 80s and walks with a cane, asks the lounge attendant for a buggy to the gate (which is far away, other end of T4). They reply "You don't really need that, you can walk to the gate" when he has trouble walking to the desk in the lounge. They don't know he is traveling with me; I walk up (fit young man who has no need for the buggy), and they immediately say "we'll order the buggy right away sir" (those days took me through the Concorde Room several times a month so most of the staff knew me by sight). I, having no need of the service, was deemed worthy of it (due to frequent flights in F on BA), while my father who needed it, and had a BA F ticket but had never been in the lounge before, was deemed not worthy.
An absurd system, and why BA is the way it is (perhaps why the UK is the way it is). So be happy, the BA LHR lounges will forever be this way.