Apple sold the first widely-available computer with USB connections, the iMac G3.
> To replace the removed ports, the iMac has Universal Serial Bus (USB) ports, which were faster and cheaper than Apple Desktop Bus and serial ports but were very new—the standard was not finalized until after the iMac's release—and unsupported by any third-party Mac peripheral.
- https://en.wikipedia.org/wiki/IMac_G3#Design
It would not be possible for them to jump on a bandwagon they started any earlier than they did.
> The last Apple device with Firewire was produced in 2012
Thunderbolt supports the Firewire protocol in the transport layer. So this means that people who need to support a Firewire device need a dongle now. Apple used to sell the adapter, apparently it's been discontinued, but they're still manufactured by third parties, and the originals available on the secondhand market. Which, given that Firewire is dead and buried, and no one is making new Firewire stuff, is also where you'd need to go to get something expecting Firewire to begin with.
I do not see this as the problem you seem to.