I would be more tempted to try this if there was a demo board that could be viewed and interacted with without having to sign up. I am wary of giving my email address before I can even see a basic example working.
I tend to think similarly, but there are many ways to generate a temporary email address.
It isn't the case here but site/app makings take note: this is why I never "sign-in using <social media account or some such>" so if that is the only option you offer I won't be trying your service/app/other.
For email I have a sub-domain set as catch-all and give out addresses in that to new sites. If an address starts getting junk I can just block it. If the sub-domain as a whole gets deluged then I kill it and start another (any site/app/other I continue using gets given an address on my main domain so I'd lose nothing, though I've never actually had to do that). Because it is a sub-domain it gets skipped by junk mailers guessing commonname@domain.tld addresses. Some sites have bad email address checking that rejects something@sub.domain.co.uk (I assume their regexp doesn't like the extra dot in the server name) but if someone gets that wrong I don't trust the code in the rest of their app so I move on.
Then it comes down to wether you are interested enough to go through and create a temporary email to check it out. I was not that interested and rarely is.
The catch-all means I don't have to create an address - just make one up on the fly. Everything to that sub-sub-domain (aside from those addresses blocked because they've attracted junk mail) are forwarded on to one of my "real" accounts.