Although I kind of take your point to a small degree, comparing vehicle tyres to cycle tyres is like comparing apples to oranges. I feel I can knowledgeably comment, as a cyclist myself, that there are a totally whole different set of criteria involved in cycle tyre pressure compared to vehicle tyre pressure. I'm not even really sure there is a cross over, the design and physics of each is totally different.
I doubt very much that Toyota have any input into a tyre manufacturer's max sidewall pressure that is stamped on the tyre.
The only correct pressure is the one where it is neither under-inflated nor over-inflated and the only way to work that out is to examine the tyre tread wear pattern on a regular basis. Like I said previously, the placarded pressures are a recommended starting point, as it can in no way cover all makes and models of tyre.
Also, remember that the internal pressure of tyre changes with the weather/temperature and season, so regular checking and adjustment, by the prudent car owner/driver, is necessary to keep the tyres optimally aired.