IIRC, aluminum cans do have a varnish liner that's supposed to be tasteless. It's possible that Mr. Michaels is one of the few people who can taste it.
Big problem with glass is degradation due to light. Clear bottles are the worst, green bottles are better, brown is a little better yet, black/opaque would be the best.
As far as I know, there's no difference in process prior to the canning or bottling stations. Bigger brewers will run the beer through a fine filter. Carbonation, then fill and cap or fold the seam over. Wash the cans or bottles, maybe pasteurization, then labelling.
Bottling used to be really the only single serving container practical for the home brewer. There's a machine shop in the Milwaukee area that's producing a can sealer that's almost affordable for the home user. My local tap room has the automatic version and uses it for "crowlers" instead of bottling. Crowlers are 24oz (ish) aluminum cans, and they've had awfully good luck. They'll even make up crowlers on demand if the cooler doesn't have what the customer want.