"Should everything remain 'online and virtuaI' come the start of the new academic year, I think you are right to suspect that many students may choose to defer if they're on the point of heading off to university."
Yes I agree with myself! - although conversely, what will those students do instead in the gap year? In the hypothetical situation that universities aren't going back 'properly', I think it can also be hypothesised that jobs will be very scarce, travel difficult/impossible, and how many can afford to volunteer/do nothing for a year? (sorry if I'm repeating myself, i've definitely said this on another thread if not this one!) It's an important macro issue though because with about 500k? potential new undergrads, that could be a significant addition to unemployment problems and university financial problems if a proportion of them decide against going after all.
On whether existing students will drop out, I have recently sensed on mn (though not elsewhere!) that there may be some disillusionment with the 1st yr experience even before this, partly added to by the effect of the strikes (not expressing a view on the merits of those, just on the effect on students). Those soon-to-be second years who might have carried on in normal times may just throw in the towel if asked to pay another £9k for on-line. (Though, again, what opportunities for them elsewhere?) Again, an important issue in terms of unemployment and university income. Presumably this is all being discussed quite keenly.