This was an active topic of debate back in the days when people still relied on modems. T1 gives you 1.544 mpbs "bandwidth" but the fact that it's "guaranteed" bandwidth means it should be fast enough for anything you'd need to do as an individual user. If you had your own private T1 line all to yourself, the latency should feel the same as being on the same local LAN as whatever service you're trying to access. Even a 56k modem still had a small but noticeable latency, especially if you're doing command-line where you expect echo-back on each character you type.

People don't really understand the speed vs. bandwidth debate, but they do know the psychological difference when latency is low enough to be unnoticeable.