Not wrong but too focused in on the resource management element.
Yes it encourages speed because you risk running out of or behind on resources, but it misses what the exact application/need for that speed is.
I would say the primary factor driving micro (and thus people away from RTS) is the potential pace of the game.
To explain what I mean let's look at DotA2 - a great comparison because its already so close to RTS games in terms of perspective and interaction, but you can find analogs for this with every other non-RTS game.
The key differences between DotA2, any other game in general, and any given RTS are the limitations imposed on the player.
In DotA2 you have a maximum move speed that limits your interactions in the game (outside of a few very specific cross-map skills).
In an RTS 'your' move speed is as fast as you can click on the minimap (or otherwise use the camera controls), and your move speed in terms of 'interacting in the game world' is how your units are positioned around the map.
What does this mean? To go faster you need to build more units, and spread them out all over the map. While there may technically be an upper limit on how fast you can interact with two disparate parts of a map in Starcraft, the reality is that the only limit is self-made: You didn't have units there. The only way to have already had units there to jump to and control is to have already BEEN controlling those units into that location.
It's easy to see how that logic degenerates into "You must always be controlling all units at all points on the map" - that sentence is the baseline theoretical skill limit in any given RTS. And that's before throwing in any considerations for unit match ups, terrain, etc.
Games do exist that flip that proposal on its head however, by making "control" itself a resource. This post is near limit so I'll just say Graviteam's Mius Front as the main example. Micromanagement is front-loaded into an un-timed deployment phase.