Nobody wants downtime, but it's easy to spend too much effort on avoiding it, taking time from actually important development. Plenty of customers don't mind occasional downtime, and it can mean the system is simpler and they get features faster.
Too much power to architects worsen the situation because they both have formal responsibility to keep the downtime low, but they are also appointed to finding technical solutions rather than sometimes technically mundane product improvements.
Also in the worst case, this solution becomes so cool that it attracts the best developers internally, away from building products.
