you can make great game with Construct 2 but you have 0% guarantee that it will work well on any platform;
and 99% issues are because web browsers are not created for playing advanced games. That's why we have situations like jittering Chromium (and then Node-Webkit and Crosswalk). That's why C2 games usually use only 1 CPU core.
And if you will have any problems - just can just report the bug to some 3rd party company and wait for their mercy. And loose a few months waiting for bug fixing.
That's why Construct 2 is a wonderful toy, but it's not a professional game development tool.