consumer unifi package is dynamic IP based, until now you will be assigned a single public IP address which is not shared with other unifi customers until the lease over or until your PPPoE session terminate.
moving forward, you are not assigned to one particular single public IP address, but instead any connection that you made will be under random group of IP addresses, this sound fine if you are just a client of a service, but if you are hosting a service/or act as a server, there the problem will came, no more incoming torrent connection, mo more P2P game server, non cloud based CCTV and alot of stuff.

Public IP is like your house phone. Call your num get to talk to you direct.
Only you (exclusive usage).

Private IP is like big office extension. Calling main line num still need to press extension #. The main hunting line is shared by whole office few hundred ppl.

The meaning of public and private is terbalik if you read it literally.
In IP, meaning of public IP is that in publicly accessible area only you will have that IP, no duplicate. Wherever u call +60162990000 still the same yellow man will pick up.

Private IP meaning not accessible from outside world. So this range of private IP is used in everybody's LAN.
U can say its like private extension. 10000 people also have extension #366

imagine this.

previously:
u got mobile number. 012-3456789
whenever outside people wan to reach u, call this number sure they know is u gonna pick up, cuz it's your cell.
when u cal out to people, they see this number, they also know is u calling.

now what TM wants to do:
u no longer hav your mobile number.
instead, u share a single company land line wit your colleague.
when u call to outside world, outside people only recognized this number is company A, but doesn't know who exactly is calling.
when outside people wanna call u pulak, will reach company receptionist first, then receptionist divert the call to your extension.
outsite people dunno your extension, only receptionist knows.

TM said browsing service is not effected, same performance.
that's a whole lot of bullshit & big fat lie.
u introduce overhead, delays, a point of failure cuz traffic need to jump through another layer to get to u.

now imagine, company introduce new rule, employee can only make approved work related calls.
u wanted to make a personal call to your wife to check on the kids.
receptionist says, "this number is your spouse's number, not related to work", & drops your call.

go figure.