You can't blame it solely on blocksize. Throughput is based on vehicle size times the number of vehicles per hour. Increasing the number of vehicles provides a far better solution that creating lumbering giants.
Your analogy doesn't work in real life or in bitcoin.
Increasing the average size of vehicle (as long as that vehicle is nearly fully loaded) is significantly more efficient and a better solution than increasing the number of vehicles on the road. Buses, trains, and airplanes (when nearly fully loaded) are far more efficient and create far less congestion, collisions, and parking problems than an equal carrying capacity of small vehicles.
Increasing the average size of bitcoin block is more efficient and a better solution than increasing the number of blocks in the blockchain. Larger blocks contain more transactions per kilobyte of blockchain, and have less orphaned blocks, than the same number of transactions spread across more blocks in the same amount of time.