To be taken seriously, Construct needs a major makeover. Their website, logo, mascots, and how they advertise their engine all seem too playful. Don't get me wrong, it's professional, but their design language is truly geared towards young children.
If Construct wants to appeal Unity users, it must undergo a complete re-branding. Construct has trapped itself in the "no-coding - fast prototyping" niche since the very beginning. And Construct 3 went full kids mode but with a hefty monthly price-tag.
So while aimed at kids, kids usually don't have any income, making schools the main target audience. Unity is aimed at an entirely different market. Even if C3 is capable to take over a small portion of Unity 2D projects, it's just not advertised as such.
Just compare the C3 landing page to Godot, Unity or CryEngine. C3 advertises how many users it has, and how the cutting-edge technology makes it run in your browser. It then starts to talk about "Chances are you've played games made in Construct and even have some installed on your phone.". Or "It's Fast". Does that sound appealing to a Unity, or any serious user?
There's no real info on what the engine its truly capable of. No technical details. No proper game showcases. I would prefer the Construct 3 Features page as landing page, because it actually tells you some important information. Not perfect either, but much better.
I think Construct does many things really great. But being appealing to a mature audience doesn't seem to be part of their marketing strategy.