Sounds like a good idea. Templates have pretty much taken over web design, it makes sense that it will take over other run-of-the-mill categories of design (where hiring a custom designer doesn't make sense).
Definitely a great service, it doesn't surprise me it has so many users.
I wouldn't be surprised if a lot of people just signed up to check it out and if a lot of other users registered multiple times with different emails to have access to the free trial.
So we'd expect Canva to have a lot more users than Hootsuite.
Also, they've raised over $80M in multiple rounds from top VCs including Sequoia [3], which would be hard to do if they were bullshitting about their numbers.
[1] https://www.alexa.com/siteinfo/canva.com?ver=classic
[2] https://www.alexa.com/siteinfo/hootsuite.com?ver=classic
[3] https://www.smartcompany.com.au/startupsmart/news/canva-50-9...
And even moreover a news story saying that 25,000 users data was stolen is not a big deal. A news story saying that 1 billion users data was stolen is a big deal. And then brings up the obvious question of whether the stolen data is really real in some way.
Facebook says ~17 million fake account creation attempts per day[1] (that they catch after the fact), so it doesn't seem that unusual.
[1] https://news.ycombinator.com/item?id=20000235 (3B/6 months == ~17M/day)