That's not actually tiling, is it? To me that reads like fullscreen with workspaces.
If one uses a manual tiling window manager like i3 or sway and a large monitor one can divide the screen into separate work areas that each host multiple applications based on their role in one's workflow and use less workspaces.
Scrolling makes a similar but different workflow practical on small screens where flexibility matters.
Pixel perfect means it looks EXACTLY like the design comp.
It goes completely out of the window if the browser window isn't the exact size of the mockup.
You might charitably say that pixel perfect means that the implementation intersects with the design comp at some specific dimensions but where are the extra rules coming from, then?
It's an archaic term that conflates the artifact produced by an incomplete design process (an artist's rendering of what the web page might look like) with the actual inputs of the development process (values and constraints).
Mobile is completely hamstrung, all of the effort went into creating as much vendor lock-in as possible rather than into creating a useful pocket computer. There's all this cool tech on and adjacent to mobile that you can't actually use in any meaningful way because every aspect of it is someone's money patch and they don't want to work together.
It's one of those things that people who haven't experienced simply wouldn't know to ask for. Wii had motion aiming but it was more of a gimmick, it wasn't until playing FPS games on the first Steam Controller that I, personally, realized how much more playable and comfortable gyro aiming made these games-- coming from mouse+keyboard, I found fine-aiming challenges on thumbsticks to be very uncomfortable.
Gyro aiming completely solves both fine aiming and tracking aim on a gamepad when paired with some kind of touch sensitive control for enabling the gyro (natural recentering).
In console FPSes they just automatically track the enemy if they're near your crosshair and call it a day-- giving everyone an aimbot instead of solving the UX issue.
Move the browser to the side? I can never understand why anyone would want to manually shuffle windows around as a disorganized stack.
From my perspective the desktop metaphor UX was obsolete the moment it was conceived of. All anyone has to do is look at the physical desks of a thousand random people and it should be immediately obvious how little value there is in recreating that chaos.