I'm scheduled to do a WDW stay then cruise in September and as long as Disney is open for business I'll be there. It would be a shame if restrictions are in place but we're plan a slower paced trip anyways, so that doesn't really concern me, we'd still make it fun.
I think I'm a lot more relaxed than most though. I work overseas a lot and had to travel back from Rwanda to the UK through 4 international airports and did so with my Husband and an infant without a face mask. We kept distance as much as possible, although on the plane this was near impossible. We also regularly washed our hands. We are all fine and are well outwith our self-quarantine period.
I've worked all over during health crisis including Ebola, it's part of my job and as long as your being sensible and taking precautions, such as washing hands regularly, I've never had reason to worry. However, I'd caveat by saying, I am healthy with no health conditions.
I personally don't believe a vaccine will solve this, we have a flu jab but there's still flu. I think a jab is much more likely to benefit a vulnerable demographic than me.
One of the most shocking things for me when travelling is that in Rwanda I wasn't allowed into the airport building without a temperature check and completing a medical questionnaire. However, when coming into the UK there was no one asking where I had come from, taking temperature or even asking if I feel well. I was able to walk through both London Gatwick and Edinburgh without question...so no wonder things got so bad in the UK!!!
The only thing that would stop me travelling is if myself or one of my family started showing signs or our temperature shot up (we take morning and evening readings at the moment). Maybe if there were significant closures still in WDW I would re-think. Otherwise Disney here I come