The art looks very rendered, with pixel cleanup in something like photoshop. I was using 3ds Max on my norma PC circa 2001-2002. Game studios should definitely have had 3d studio in the mid to late 90s on their actual workstations if they were Windows based (or lightwave). Crucially, The Sims (3ds max) released quite close in time and we know 4k was also 3dsmax, so I think it’s fairly safe to say Maxis was a 3ds shop in this era. It was ubiquitous in pc gaming of the era.
In the 2000s SC4 was already using 3DS Max, but here we are talking about a game that started development in 97. And they already had 3D games before it...
In SC3k sprites you can also clearly see two different grid sizes, so at the very least the retouching and some props are "pixel art".