Here's the non-standard (and thankfully obsolete) 30 pin connector.
Translate the pin-outs into standard connectors.
Summarising, there's two line level stereo analog pairs, in and out. The standard connectors for those are RCA jacks. So we have four of those standard connectors.
S-Video standard connector is a mini din. There's another standard connector.
Firewire (you'll note the pins assigned to that) is another standard connector.
USB channels (again, you'll note the pins assigned to that) is another standard connector.
Just to facilitate the non Apple standard protocols, to make the 30 pin connector, "standard" connectors would mean:
4 x RCA Jacks (Arguably these could be reduced to an additional 2 x 3.5mm stereo pair line level jacks, in addition to the headphone jack)
1 x S-Video Mini Din
1 x Firewire Port
1 x USB
That's ALOT of standard connectors.
Which no phone ever made has ever had. Not by any manufacturer. Ever.
Of course the 30 pin connector is an outdated example. People complained about it being get rid of (owners, had to buy more accessories), and other people complained about it being introduced to begin with (non owners, not affected, got angry anyway).
There are several stories around "Apple just makes weird connectors" that don't quite pan out. The 30 pin connector shows that. It can't be translated into "standard connectors" without a myriad of "standard" sockets that no phone could accommodate.
(Personally, I think removing the 3.5mm headphone jack sucks, but that's a different than 'that's what they always do'. It just sucks.)