I don't think you understand the physics behind sensor and lens design.
In any case, OEMs make more profit out of lenses than bodies, so having small lenses in a small market segment is not that attractive. Small sizes tend to come with fixed lenses, so interesting to see the Fuji GFX fixed lens launch. If Sony launch an RX1R iii, that will be a sign of their view on the market.
Would you want much smaller than existing offers?

Panasonic 12-32 (would get today as G100D kit or fit to EP7)

Panasonic 35-100mm kit
[ATTACH alt="OM 12-45/4 - absolutely not a "kit" lens but sold as a kit "]3660412[/ATTACH]
OM 12-45/4 - absolutely not a "kit" lens but sold as a kit
View attachment e3aab5113f9b4714b5a6baa645bbd882.jpg
The Olympus 40-150mm R looks big compared to the Panasonic but small next to the 40-150/2.8
The Pro 40-150/4 is only slightly larger than the kit R.

Panasonic 20/1.7
Look at the Sony FE 28-60mm kit lens, which is optically excellent, or the f2.5 primes, or manual primes like the TTArtisan 25/2.
Small sensors have an AF advantage because you have the same light over a smaller area for similar lens sizes (apart from fast ultra-wides), so you can AF in lower light. MFT might be the sweet spot, especially with the QBPDAF array in higher end bodies.
I think that phones occupy the small sensor market very well.
Andrew
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Infinite are the arguments of mages. Truth is a jewel with many facets. Ursula K LeGuin
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