Traditional facilities optimize for customization and long operational life. Modular designs trade some of that for speed. The specific reliability question at scale is thermal and structural performance of modular joints under sustained high-density load. Not a theoretical concern, but workable with the right specs.
The timeline advantage is where the math gets interesting. 90-120 days vs. 18-24 months for traditional construction means capital deployed faster and the customer pays rent sooner. On a $50M project, shortening the non revenue period by 12 months at a 7% cost of capital is worth something significant.