Never say never but this is very very unlikely to happen. There are already many types of software that are specifically designed for this purpose, so there's no way we'd be able to compete with them.
Yes, there're so many software for this. And there're so many Visualization and rendering softwares, but how come this Lumion could have your own market nowaday ?

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Even nowaday, there's still not even one software that can really solve Landscape architects problems easily. No any software in the industry do quite accurate representation and included realistic physical planting data in them.
To me, Lumion is being SketchUp-like on rendering side. How come SketchUp being more used by a lot of architects than 3ds Max nowaday? To me, an easiness and versatile is the key. It's like apps vs. softwares in many cases. People tend to use easier and quicker tools more often than powerful but complicated one. I'm not means Lumion can't be big, but simplicity should be remain and offer something no one like. I'm not means feature vs. feature, but an overall workflow feelings. Lumion quite eliminated rendering set up and processing time, and a lot more thing can be eliminates on presentation phases. And it will really empowered architects more and more. No pro design or rendering software can really achieved this at the same time. That's how Lumion can grow without being direct competition with big companies.
For example, currently there're no any architect-oriented software that can do quite accurate environments such as landscape, road or cityscape easily. They need civil3d, GIS etc file from someone, which all are not design really well for architects. They have a lot unnecessary aspect and tools which architect don't understand. All architect-focused softwares can do typical modeling easily, but their detailed or accurate environments set up are time consuming. That's a big niche I see that go along very well with unique fast animation and final touch abilities of Lumion.
I imagine I can just finished building, hard surface stuffs, some landscape sketches in revit, import rough surrounding dwg. Then spend very little time to drop in and get quite completed animation environments and other aspects set up in Lumion.
I bet I can't be back to V-Ray if that happened. I'm willing to sacrifice some quality. Because I dislike labour intensive and time-consuming process. And I think I'm willing to spend time more on Lumion when more quality is needed (sure, Octane-like plugin for Lumion would be even more nice. IMO Lumion+Octane synergy seem superior to even V-Ray for 80-90% of work already. They're so cheap and Lumion even able to monetized them). Lumion give something I can't get with my typical V-ray animation workflow anyway

, for example those animated sky, water and trees. They need too much horse powered to me (and sure for many others). I feel Animations on Lumion can give life-like feeling with little time compared to V-Ray.
And to solved competition problems. Make selected cools and nice softwares, not necessary all, pluggable to lumion and it could be one of a kind software.
“The best way to destroy an enemy is to make him a friend.†- Abraham Lincoln
Regards,
Ming