Professional wide angle zoom lenses tend to have apertures of f/2.8, but for photographers who do not need that extra light-gathering power, choosing an f/4 zoom can mean significant savings in both weight and cost (and sometimes other gains). For Canon shooters, there is the RF 14-35mm f/4L IS USM, and this great video review takes a look at the kind of performance and image quality you can expect from it in practice.
Coming to you from Christopher Frost, this excellent video review takes a look at the Canon RF 14-35mm f/4L IS USM lens. While professional wide angle zoom lenses typically top out at f/2.8, people like landscape photographers might not need that extra stop, and the extra 2mm on the wide end might be quite appreciated, as the difference between 16mm and 14mm is rather significant. Along with that extra reach, you get image stabilization, making this quite a versatile option for a variety of applications, particularly landscape photography, where focal length versatility is often more prized than a wide maximum aperture, and it sure looks like it delivers the goods. Check out the video above for Frost's full thoughts on the lens.
"professional wide angle zoom lenses typically top out at f/2.8,"
Premium priced wide angle zoom lenses typically top out at f/2.8.
That is what the phrase should read.
A pro lens (if one can really describe one) would have optical and build quality that makes money for decades. Interestingly, that covers a ton of lenses available today irrespective of price and badging.
Those fixated on maximum apertures tend to be amateurs and are prized for their free use of their disposable income and thus the target of these "pro-grade" lenses.