Sure, icons on the desktop, or just about anything in a file/app explorer window, require a double-click by default, because the lineage of the main desktop area is just a file explorer window without the window decorations.
I think it might be about stakeholders wanting the web to "feel" more native and interactive. Double-clicking to "go" feels too much like you're interacting with the web as if it's a file browser. They want it to feel more immediate?
In principle I'd prefer the consistency of double-click or double-tap everywhere, but I'm used to adjusting based on context. Wouldn't double-tapping annoy everyone who primarily uses mobile devices?
If consistency between systems is more important than usability, it probably makes more sense to use single click to open in the OS (which has been an option in Windows for 30 years).
The real problem IMO is that we have effectively standardized on two-button mice as the baseline, with all UX then designed around that even though many mice have 5+ buttons these days. The three basic actions that desktop UI has ultimately converged on are: select; activate; show additional actions (context menu). These should logically map to three independent buttons, such that the two most common actions are mapped to buttons that have fingers resting on them in neutral position - e.g. left = activate, right = select, middle = context menu.
At one point round about Win98 Windows took inspiration in the other direction, with Active Desktop: you could change a setting and have single-click to action in Explorer.
Users of just the web are not fully computer literate. The interface is super easy compared to actual programs where you need things like menus, right clicks and full hotkey support.
If I think back to how my mother struggled with computers and how her friends were just as useless, I think they would be stumped with having to double click. Arthritis comes along too, so that generation needed all the help they could get. Generally it was only the advent of online shopping that enabled them to persevere with giving things a go.
That is some Windows UI stuff, If I recall correctly in OSX you don't double click as much.