"we offer IPv6 and nobody except Googlebot uses it."
And your target demographic? Lemme guess, cat videos. Auntie Mabel reading her e-mail wouldn't know an IPv6 from an IP Freely.
For the rest of us, there's IPv6 or CG-NAT. The choice is yours but don't come crying to me when you can't run a simple e-mail server on your endpoint because it's behind multiple layers of unpredictable NAT and the incumbents have you stitched up like a kipper. Want your own domain? Want to access that NAS from the wider 'net? Need to run a VPN? KER-friggin'-CHING!
Follow the money, son. YKIMS.