From what I've read ordinary passenger vehicles put just about no strain on modern roads. Only heavy vehicles like semis do.
Tax is tax, money is fungible.
Tax is tax, money is fungible.
Why should I be taxed to fix road damage based on a metric that doesn't begin to accurately reflect my actual contribution to the problem?
Additionally, if the trucking industry had to raise rates due to a higher 'road maintenance tax' this may also make more efficient forms of transportation more popular, ie trains.