It’s clear by now that the virus is generally not that dangerous for 0-17 year olds (with exceptions aside). Plus: whether there’s a second wave or not, it’s still going to take a while. I’d take those two facts into account when making your choice.
With the visit, I’d certainly not take too many risks, but I think I look at it more freely than the first reaction. How big is the risk, for example, that grandma and grandpa catch it in their daily lives? If they don’t work or work from home, that’s very manageable and they might be able to come by occasionally. And what about brothers and sisters?
Beyond that, I wouldn’t go any further, because the bigger the group of people, the greater the risk for grandma and grandpa (who, due to their age, often face a higher risk). And the rest won’t miss it that much anyway.
I would think about it: if you prefer to keep your distance, how long do you want to maintain that? If you don’t want them involved right away, you can offer perspective and give them something to look forward to. And by then, it’ll be easier to return to some contact; otherwise, you might keep putting it off. Keep in mind it could take years, and you can’t keep him/her inside forever.
Anyway, no one will be angry about your choice!

So do what feels best for you.
I was due in August and will take another critical look by then. But here’s how I see it now:
We’ve chosen to allow grandma and grandpa in (they don’t work/work from home). We’ll make sure they wash their hands well, but they’re allowed to hold him. Brothers/sisters only if they haven’t been to work for at least 2 weeks and have been careful (in practice, this means my sister is coming because she really wants to see him, but my husband’s brother isn’t). The rest aren’t coming in. I’m also keeping my still-living grandmas at a distance, but that’s because they’re around 90.
After 3 months, grandma and grandpa have to choose. They would babysit for 2 days and he’d be at daycare for 2 days. Both seems irresponsible for them, so we each work 1 extra day from home. It’s up to them whether these are their babysitting days or the daycare days.
I’d most like to protect him from everything, just like in the reaction above. My dearest little one

. But that’s not possible. You have to do your best, but protecting him from everything isn’t realistic in my opinion. And for us, the relatively low risk for babies plays a big role. Otherwise, no one would come, even if I had to stop working!
Where are you leaning now? Good luck with the choice anyway!!