DV Capture and Firewire Capture for Premiere Pro Removed?

There is absolutely no chance to get that capturing back. You see, recent versions of OSX have depreciated and/or eliminated Firewire support altogether. And rubbing salt into the wound, Apple systems sold in the last five years now no longer support Firewire at all, nor can Firewire be added on at all. So you will have to stick with a system that's more than seven years old just to even support Firewire at all. Unfortunately, the older hardware has now fallen well below Adobe's minimum hardware requirements to run Premiere Pro properly (that is, now require a system whose oldest core hardware component is no more than two generations old). Adobe, in this case, had absolutely no say whatsoever about this. And any hardware that's either vintage (legacy) or obsolete at the time of the release of a given version of Premiere Pro will no longer be supported at all.

The only alternative there is to switch from Mac to Windows. And even there, not all add-in Firewire cards are compatible with Windows 10 (the only Windows OS version now supported in Premiere Pro).