I had to turn up the volume for the cutscenes. This was the first indication that maybe this wasn't very good. It's worse. Grey Goo is honestly rather embarassing. But let's say some nice things first.

The good

Grey Goo is really beautiful. It has some of the CGI i've seen and the game itself looks nice too. The Goo look great and the way their economy works is quite interesting. Some of the units have interesting designs too, like the bomber plane that uses other units as bombs or the artillery unit that fires some sort of creatures.

The upgrade system is also somewhat nice, it can really change the way you use some units. But it's overly restrictive - you can only have 6 (?) upgrades in total.

The bad

Ok, so pretty much everything else is bad. You can't rotate buildings before placing them. Instead of using the fog of war to restrict building they use line of sight. Want to build an extractor? You need a unit to provide LOS even though you've already explored the area.

The Beta and Humans use a terrible terrible system to restrict unit construction. Instead of just building a tech-unlocking building somewhere you need to build these attached to factories. It's tedious and annoying. The same goes for all construction for the Beta and their awful hubs. The Humans are even worse because everything has to be connected with connectors. It reminded me of the power system the old Command & Conquer games had, which makes sense since the same people made this game. You can't just build a refinery, you have to build a hub/connector and hope you've placed it right. Ugh.

The Goo and Shroud are the Zerg and Protoss of this game. The Goo spawn units from movable eggs. The Shroud require pylons to unlock all units in a building. The first works fairly well, the second is just an annoyance. StarCraft had these very simple, sensible restrictions to building (pylons/creep). Grey Goo turns construction buildings into a tedious annoyance. It's also confusing, i have no idea how to make a Human factory with all 4 tech attachments.

Another mistake was giving each faction the same basic types of units. Infantry, anti-armor, anti-air, tank, artillery, siege. The result is that despite their differences the factions feel too much the same. There isn't even the basic health difference StarCraft has. Humans need to repair, Zerg heal slowly, Protoss have shields. Here everyone works more or less the same when it comes to survivability.

The ugly

The game is boring. Especially playing as the Goo requires tons of waiting. There's very little in the way of tactics, combat is mostly about numbers. Units don't attack nearby enemies hidden in the shroud. You can only queue 3 units in factories. If you set them to an infinite loop they sometimes stop for some reason (???). Unlocking bigger hubs/factories requires owning a smaller one.

What finally made me quit was the third mission of the main campaign. In most missions the enemy has huge defenses apparently, but the jump from the previous missions was insane. A group bigger than the one i used to crush the enemy in mission two barely made a dent in the defenses now. So they want you to spend like an hour building an even bigger force before finally attacking. But, wait for it, there's an earthquake every 5 minutes. And after every quake you have to manually repair the dozens of buildings and attachments you have all over the map. Wow.

Conclusion

There's a reason why RTS barely exists as a genre nowadays. These old Westwood guys failed to learn from StarCraft 2 and other modern games, they're still making C&C/Red Alert like it's the 90s. Not only that, they even forgot how to do that right. Grey Goo is simplistic, tedious and boring, with a lazily designed campaign that just gives the enemy huge defenses to artificially lengthen game time. Such a waste of beautiful visuals and an interesting story.