[justsomehnguy]

> an IPv4 address is decent to remember and while DNS is useful, the issue sometimes is DNS, in which case you need the IP anyway

It's like rambling about absence of crank handle on modern cars.

> why colons

Because dots are in the DNS.

> why do it in hexadecimal format

Because it's shorter than decimal and you can't nest decimal representation without some delimiter, eg 1220 -- is this 12 20 or 122 0 ? Cue in 'but why colons'

> DHCP is a good thing, why is it maligned? a central source of truth who is what is great

No, it's not. And definitely it's not source of truth. A client can ask, DHCP server can provide an address but if you don't have an address in DHCP leases that means nothing. And even if you have that doesn't mean that this is still the same device.