The loss of public lavatories is indeed a long term problem that stretches back before the 1980s: once upon a time public conveniences routinely charged for use, and thanks to lower costs and relatively higher charges could be self supporting; the standard one penny charge in Victorian times would be equivalent to about 50p in 2020 (higher than most current charges), and the revenue from a single (attended) Victorian convenience could be the equivalent of over £20k today. But costs rose while charges stagnated, and the Turnstile Act of 1963 effectively prevented councils for charging for urinals, making it difficult for councils - of any political hue - to charge for public loos at all without discriminating against women. The act's financial redress for councils was removed in 1981.
That has made conveniences a steadily increasing burden for councils (who even had to pay business rates on them until recently) and an easy target for cuts. Add to that the difficulty of making them accessible or addressing a long-term backlog of maintenance and refurbishment, plus 'anti-social behaviour' of all sorts dissuading people from using them, and you have a perfect recipe for closure that has seen public loos dwindle since the 'seventies, with an acceleration of closures during 'austerity'. As an example, there were 65 conveniences in Glasgow in 1970, and just nine today (which is eight more than Manchester).
As for Coronavirus, surface-to-hand-to-face transmission of any germ should be something is limited within a convenience if anyone has an ounce of common sense: to touch your face after touching the surfaces in any lavatory at any time risks infection from all sorts of bugs; and hands should always be washed before leaving (cue eye rolling/guilty looks - but it's a civic duty now!), though automatic handwashes may need to be adjusted to allow longer washing cycles. The principal transmission vectors are likely to be the exterior doors and atmospheric droplets. The former can be mitigated by propping the doors open; the latter is much more tricky. How do you ensure that the fresh air circulation is sufficient to prevent germs lingering in the air? And even if you limit the spacing at the urinals, it is difficult to keep six feet apart while moving through the circulation spaces, using the washbasins etc. How do you know how many people are already inside a convenience before you enter? That's why it is being suggested that there will be a move to single-compartment facilities in the future, possibly with basins outside. If councils/central government can find the cash or will to do so.
Public lavatories are desperately needed by many people, whether due to medical needs or simply because they work outdoors or have no home to go to: they ought to be properly funded and available to all. We can surely afford to give people somewhere to perform a biological function that they cannot avoid. In a civilised, relatively prosperous, society it ought not be a choice between dignified urination or social care.