I don't want to be overly semantic or PC on HN, but just saying the GP may be female, judging by their name on profile. Being misgendered could be very offputting and discourages participation, so you may have wanted to say "this person" even if it doesn't sound as offhand as you'd have liked it to come across.

- Macro: resource prioritization (army vs expansions vs upgrades), scouting to understand the opponent's macro choices, choosing the right posture in response (defensive, harassment or offensive), and resource optimization (not getting supply blocked, scaling production with income, increasing income at the maximum possible rate, removing bottlenecks, etc), scouting the enemy army composition to prepare the ideal counter army composition

- Tactics: Grand army decisions - flanks, baits, sneak attacks, hiding composition, multiprong attacks, positioning of siege units, timing attacks, knowing when to retreat (hit & run), scouting to gain advance notice of your opponent's tactics

- Micro: optimizing unit lifespan and effectiveness within an isolated skirmish for the given goal (usually to 'win' the engagement) -- pulling back weakened units to avoid aggro while it still deals damage, healing, surface area for melee units, trapping enemy units with terrain or skills, optimizing spellcaster energy usage, prioritizing targets based on multiple parameters (range, damage, cost, count, follow-ups), etc.

AI can "run" macro well, but they are poor at the macro decision-making part, which includes priority model as you mention (the responsive posture choice above and others). Up to low grandmaster tier, being significantly better at macro than your opponent while close in tactics and micro is usually enough to win consistently. It is the most impactful part of an RTS (and is where most of the 'S' lies).