I'm not super familiar with BAR but most I've what I've heard about it makes me feel it fell flat as a game. I was never interested in it personally because of theme.

Looking at the games I like, I don't think I agree that 'developers can't get out of the mindset of "rock paper scissors" strategy' is a valid critique. First, I don't think it's even entirely accurate. A game like Age of Empires 2 doesn't have a simple RPS system in reality; that's just a simplified explanation we use when first getting into it. In reality, spears/scouts/skirmishers form a pretty good RPS, but in large numbers ranged units end up outplaying cav with good micro. Then there's units like siege and the non-spear infantry units which don't fit neatly at all.

Age of Mythology superimposes a second triangle over the basic triangle, in the form of the hero/human/myth unit triangle.

And all these games have broader strategy triangles in the form of boom/turtle/rush. Or the eco/tech/military triangle. In AoE4, that latter tends to look like fast castle vs 2 TC vs feudal military units.

But second, even if you do simplify these games down to RPS, I don't think it's a bad thing to have that be the core of the game design. In fact, I would say just the opposite. The Age game that deviates the most from an RPS model is the least successful. Audiences, when talking about RTS games, will extol the RPS mechanics and the interactions and back-and-forth that emerge from it. Strategies like building mostly one unit, with a few of whatever counters the counter, or the benefits of scouting so you can concentrate on what counters you opponent's play, etc.

People talk about RPS in positive terms. It's commercially successful. The audience just leans towards something which can be mapped on to RPS.