The efficiency trend behind this year's model releases is easy to state and easy to undersell: getting a fixed level of capability now costs roughly a tenth of what it cost a year ago, and that pace has held for multiple years running. It shows up in list prices -- Google's Gemini 3.8 Flash, released September 2 as an agentic/coding/reasoning-optimized model, is priced at $0.75 / $3.75 per million input/output tokens, a fraction of what comparable frontier capability cost when this class of model first appeared.
The direct effect is obvious: things that were too expensive to run per-request now aren't. The less obvious effect is architectural. A lot of 2024-2025-era system design in this space treated model calls as the scarce, expensive resource to be minimized at all costs -- aggressive caching, one big call instead of three small ones, avoiding a verification pass because it doubles spend. Some of that reasoning stops applying, quietly, as the cost floor keeps dropping. A three-step plan-execute-verify loop that was a hard sell on cost grounds eighteen months ago can be a rounding error today.
That doesn't mean cost stops mattering -- it means the place it bites moves. Infrastructure investment is chasing the same curve from the supply side: Positron raised $875M specifically to challenge Nvidia on inference economics with a chip design built around commodity memory rather than the scarce, expensive HBM that constrains current accelerator supply. If that bet pays off, it's another turn of the same crank -- cheaper inference at the hardware layer, not just the model layer.
The practical implication for anyone budgeting a product: a cost-per-request number from even a year ago is not a safe planning input today. Rebudget against current pricing before deciding a feature isn't affordable, and revisit that decision on a cadence that assumes the floor keeps moving, because on this year's evidence it will.
An architecture decision made to save inference cost eighteen months ago is worth re-checking against today's pricing -- the ~10x/year efficiency curve means yesterday's expensive call is often within budget now, and the reverse mistake (assuming today's cheap call stays cheap forever) is less common but just as worth watching.