Anyone that studies different arts but can then only discuss the similarities and not the differences in any meaningful way is only providing insight into the their own short comings and not that of the arts involved in the discussion.
I've always felt that finding similarities in things tends gets you closer to "truths" than dwelling on differences.
I often use the analogy "spokes on a wheel". We can all start from different places, but our goals should basically be the same.
This applies to everything, not just martial arts.
Aut Pax Aut Bellum - Either Peace or War