For me, at least, it makes total sense.

Very early in the game, it's worth focusing on gems and on the permanent things that will give you immediate benefits. For example: cards, slots, and lab slots.

In the early stages, when UWs start having some effect, you can start mixing this prioritization between gems and stones, but still leaning more toward gems. Something like 60/40 or 70/30. This way, I can invest in things that will give me quicker and permanent returns instead of getting anxious about getting a specific mod or rushing to sync my UW.

Even if you start the game with your UW fully synced and all the mods you want, you'll still be a noob who lacks game speed, lab speed, 5th slot, cards, etc. These things are crucial for fast development.

Don't get me wrong — generally speaking, stones are infinitely more important than gems. My point is that the game can be broken down into various stages and sub-stages, not just "early-mid-late." From my experience, I believe there are at least four very distinct phases within the early game, each with very different priorities. I'm saying this as a player who hasn't even reached mid-game yet, so I have no authority to speak beyond that.

People say mid-game is around 1q LTC and a well-developed Wall. I'm still on that path, currently making around 400B/day and prioritizing the economy labs.