Point of IPv6 if PAT exists?

If this has been asked before, please let me know and I will remove it.

What it the purpose of implementing IPv6 if PAT has the ability to have multiple hosts under a single IP? For every IP that privately exists, there are thousands of ports each could be assigned to in conjunction with a single public IP for each grouping. As naive as this question might seem, I can't find an answer, and I feel stuck.

Thanks for reading.