I think that's understating the complexity of the IBC. The nice thing about building codes is that the regulators are local, but the regulations are very widely (voluntarily) adopted by those independent jurisdictions.
Local jurisdictions will usually have addenda to the code, for local fire requirements, etc., but a lot of that flexibility is baked into the standards themselves. In here there may be regulatory capture from local builders, and at higher levels (state-wide) there may be some capture from larger construction companies, but there's very little in the way of a feedback loop to allow homeowners to significantly change the building code.
Rather than debate in abstracts, I'd be curious if there is a particular section of the code that you feel is a result of this sort of capture. The IBC is available for browsing online [1], and Chapter 5 has the base restrictions on building size, with some notes on justification (largely about at what size you require additional fire suppression, which is a cost that most builders want to avoid in residential settings).
Local jurisdictions will usually have addenda to the code, for local fire requirements, etc., but a lot of that flexibility is baked into the standards themselves. In here there may be regulatory capture from local builders, and at higher levels (state-wide) there may be some capture from larger construction companies, but there's very little in the way of a feedback loop to allow homeowners to significantly change the building code.
Rather than debate in abstracts, I'd be curious if there is a particular section of the code that you feel is a result of this sort of capture. The IBC is available for browsing online [1], and Chapter 5 has the base restrictions on building size, with some notes on justification (largely about at what size you require additional fire suppression, which is a cost that most builders want to avoid in residential settings).
[1] https://codes.iccsafe.org/content/IBC2018P3