That is very strange.
Google puzzle me quite often. The Nexus strategy I could see: make one reference phone each year, generally not a spec leader but a reasonably-priced showcase for the OS. The Pixel "a" models come close to that. But the regular Pixels have been marketed as Google flagship devices but the hardware doesn't get the attention that an outfit with Google's resources could devote to them:
* The original Pixel was a dull device with huge bezels that served no purpose (no speakers, no buttons, just dead space) and lacking features people would expect in a flagship (e.g. no IP rating when they had been standard for years)
* The Pixel 2 was a16:9 design 6 months after that became old hat, while the 2XL had a below-par display
* The Pixel 3XL had the worst implementation of the notch ever (some people carped that the regular 3 had "large" bezels, but they were balanced and held front-facing speakers, I personally think the design was fine)
* The Pixel 4 has the gimmick scanner and, to make space for it, a top-heavy design, but no fingerprint scanner
I'm not joking when I say that as long as they release a 128GB model I'd take the rumoured 4a over the regular 4 any day: better design, and I'll take a headphone jack and fingerprint scanner over a pointless radar thing any day, being half the price would just be a bonus.
Maybe they'll get there with the 5 (after all, it would be very Google of them to make a fuss of the new scanner and then drop it the next year), but my guess is that they'll do something that's either strange or a hang-over from 2019.