An interesting question. When I posed the same question a few days ago on TFE Live, Tom's opinion was that the new rules would continue to go into effect on January 1, as planned. I don't think that opinion was based on any hard information.
On the other hand, I'm starting the unfounded rumor that there will be two new signals added to Race Signals, inspired by Matt Bounds and Francisco Juaregi::

World sailing will of course have to decide on this, but it makes sense to continue the normal timescale for the rule changes as just because the Olympic Games is postponed, the sport will continue to function once the current situation resolves itself.

I think they should postpone the change and maybe make the next quad just 3 years. When the rules are changed, we almost always have some small but noticeable unintended consequences from the rules changes and it would be very difficult to fix those in just 6 months, we normally don't even know they exist until the summer. The reason we have the quads and the reason that the Olympics are right at the end of them, is so that the competitors can use the same rules for their entire run up to the games. To make changes on them, that might be a game changer for them, isn't fail and should be avoided. To stick with the current schedule, just to keep a schedule, won't help the Olympic competitors. While, changing the schedule to a 3 year quad, won'y have any significant impact on the average racer.