it all kinda depends on what your view of "normal" is...hopefully there will at a minimum be a treatment available to greatly improve fatality rates, and shorten recovery times...of course a vaccine (preferably without nasty side effects) would be best.
however even if a vaccine that works 100% of the time, in everyone and has nearly 0 negative side effects is widely available by jan 2021...5 months of true recovery time may not be enough (all depends on what is/isn't on a "must do" list for a trip to hawaii)
the longer that it seems recovery will take...the more small business owners will decide to shut down (and move to a different state)...and its not just business owners...but many of the younger workers may do likewise. what would this mean for tourists next summer...it may mean that it takes longer for rooms to get turned around (so check in times may be later, and check out times might be earlier...less rooms may also be available). it could also mean that hotels and tour companies that were very good prior to the shutdown...may not be good after (as people may decide to change jobs rather than go back to where they were).
there are some things that should remain almost unaffected, and see a near instant return to what they were....beaches, parks, and museums (pearl harbor, and bishop museum) should all be fairly quick to recover. places like dole, haleiwa (all the small shops), and kua loa ranch...might not recover as quickly...if ever.
the flipside to waiting till 2022 or later is that if enough people decide they also want to wait till a "full" recovery (possibly 3-4 years)...the state may have decided to try and transition the economy away from tourism and to something else. this could mean that trips could cost quite a bit more as getting any other industry to work in hawaii requires one basic thing...lower cost of living...which would require policies/taxes to make land cheaper (so unattractive to vacation homes, investment properties, and short term stays).