Out of context, it is not clear what "point of physics" means. If I jumped into the middle of a conversation and heard just this sentence, I would assume the speaker was offering a justification for studying physics (honestly, I'd probably judge his meaning by his appearance).
One point of physics ?=? One reason why physics is valuable to know/study.
It is also possible that the speaker is using "point" as a loose synonym for "concept" or "result".
One point of physics is that mass does not affect acceleration due to gravity.
In fact, the second explanation was my first instinct though upon further reflection, I believe the first is more likely.