We don't have to touch every class of device with our B2B product, but we do have to support desktop/tablet/etc. We decided to make a tradeoff in terms of aesthetics and keep the overall design as simple as possible. When you don't plan to test the dimensions between iPhone and iPad or concern yourself with foldable/esoteric devices, you should probably not get too elaborate with your design language.
Our app has 1 simple breakpoint @ 960px. Below this, we assume we are on smartphone and run with one column layouts. Above, we display the full width view. We combine the media query with CSS grid layouts to swap between modes. The specific number was chosen to allow full-size presentation in side-by-side window arrangement on a 1080p desktop (our most typical power user scenario).
Again, we are B2B and only have to tolerate US audiences. So, we have the ability to get away with far more than developers who have to polish B2C experiences with international audiences.
If I had to do B2C web properties and ideally support as many devices as possible, I would be more amenable to that adjective. Otherwise, I would say it is a normal amount of "hard".