What is being missed is that most commercial leases are much longer term than residential leases. Businesses will want to renovate the space and sign a 10 or 20 year lease. So if you lower the rent by 30% you will really be reducing the income of the building over the long term and face those consequences when refinancing. Landlords will frequently try to rent out unused space to temporary tenants like popups or non profits that they can move in without renovation and kick our on shorter notice to generate some cash-flow and keep the storefront occupied.