It's a 1st party title, using the same engine, which has undoubtedly gone through several rounds of polish and optimization. There was some pop-in in BotW, I remember that, but it was usually when gliding across big distances. Besides, it's not like some of our time's most lauded releases didn't, and indeed still do, suffer from massive pop-in issues across platforms (GTA V says hi).
Nintendo gave up the power chase since the N64 days, and wisely so. Their own software and hardware have ever since existed as a synergetic package, to great effect. If anything, Nintendo's 1st party titles are known to be among the smoothest running in the biz. That said; the Wii U version of Breath of the Wild was damn near disastrous from a technical standpoint.
I haven't heard anyone express this fear, all I see is excitement, and I happen to share it.
As for Cyberpunk 2077; this is a 3rd party release which attempted to tread new ground in ray-tracing and vertical level-design. It also had the misfortune of releasing in the cross-gen window, needing to cater to a massively varying hardware pool. There was also pressure from the top to release it, seeing as how development had already dragged on for so long. Zelda is firmly in Nintendo-only hands, and there's no one above shouting and complaining about not getting it out on time. It's single-platform, and not cross-gen, and has the added benefit of being built on the existing foundation of the previous game (unlike Cyberpunk). The situations are really nothing alike. All things considered, it has the making to be a near-perfect release for Nintendo, both from a technical and critical angle.
Lastly, as a huge CDP fan, I have to agree with the above notions. I consider The Witcher 3 to be one of the finest games ever made, which is no small praise from someone who started gaming in 1988. But, it was not a technical marvel at release, especially the implementation of extra effects such as Nvidia Hairworks, was terrible (it more or less halved your fps on PC). I bought a beast of a rig at the same exact time as TW3:s release (specifically to max out TW3), costing me about 3500$, and could still barely cross that magical, stable 60fps limit in 1440p on ultra (running a 980 Ti).
TW1 was somewhere around "decent", TW2 was actually very good - but not amazing. CDP hadn't done all that much to deserve "best ever developer" up until Cyberpunk 2077 released. To me, their greatest achievement to this day is still GOG; adapting and selling classics in a slick storefront, fixing old bugs and insisting on doing away with anti-consumer DRM solutions.