I need to “vent" a wee bit because this is a misconception I've seen even high-end networking people repeat.
FIOS is not "bigger" or "fatter" and it does not offer "more bandwidth" or anything of the sort. Even ISPs and carriers get these terms wrong so please don't take this as an attack on you.
The term does have some relevance at the provider level but usually what they mean when they say "bandwidth" is "capacity" but that doesn't sound smart or sexy so
bandwidth gets bandied about (I blame marketing). While a FIOS link likely does have more bandwidth than, say, cable when it comes to how the end user views things, that doesn't matter much. Ham radio HF guys are acutely aware of bandwidth when transmitting because if they transmit with their carrier near the end of the legal spectrum then their signal will spill outside the legal range and they'll get a visit from the FCC. This is an actual bandwidth problem.
Bandwidth is the amount of frequency spectrum used to send a signal. Bandwidth is important in things like WiFi and Cellular because they are both radios and the spectrum is shared so a wider bandwidth means more of the spectrum is consumed which means a higher quality signal can be sent that likely contains more data than a smaller bandwidth (depending on encoding). WiFi channels on your AP (like all radios) are legally limited in the bandwidth they can consume. Some can couple multiple channels together to double the bandwidth and in this scenario the "pipe" is "fatter" or "wider" quite literally, but that's not what's happening with DSL, Cable, FIOS, Ethernet, etc.
The thing that really makes FIOS better is the fact that it's
faster. Now, bandwidth is definitely in the equation but it's so far down the stack that only electrical engineers should be worried about it. The only thing that matters when it comes to Internet coming into your premises is
speed (and latency, but for most people latency doesn't matter much).
This is all kind of amusing to me because we measure our connections in Mbps and Gbps which are literally
bits per second which is a measure of speed just like
miles per hour. This gets complicated with encoding schemes, but really what everyone wants is more speed. The faster the bits can be delivered to better your streaming video will be. Damn near everyone is streaming video these days, and if you've ever noticed pixelation while doing so that's because the bits could not be delivered fast enough. In a world where everyone want so to stream in 4K, more speed is always better.
As I said I've seen high-level networking people get this wrong. If you want to learn about bandwidth then get a ham radio license. Nothing says
nerd like a ham radio license.