(1) They most certainly are slowed down. Mail services have limited bandwidth (e.g. Christmas), and higher priority package can and do displace low priority ones.
1) Which is either where the comparison gets accurate to bandwidth without net neutrality, or breaks as a comparison with net neutrality, because then it's FIFO regardless of which service/delivery network.
2) When you say usually, do you mean globally or in the US where we're discussing net neutrality? Because there most certainly usually is a local monopoly.
> 100% of all developed US census blocks have at least two broadband providers.
That's false going by your own source. Broadband requires 25Mbps/3Mbps [1] (even if I personally think even that's low), and 58% percent of developed census blocks lack choice there, of which 21% can't even get it.
The truth remains that if you want broadband, you're in a majority of cases locked to a local monopoly. This is what net neutrality fixes. Until local monopolies can be dealt with at least.
2) Do you care to expand on that with reasoning or logic?