[Melkman]

On the contrary, the numbers of routes decline. Since you get a single IPv6 assignment, often a /48, you can summarize all your networks to that assignment. IPv4 is a mess in this regard. Small assignments to ISP's and businesses were made to be frugal and delay address space exhaustion. This has caused the address space to be very scattered. You can see at https://bgp.potaroo.net/index-bgp.html that IPv4 has about 900k advertised routes and IPv6 has about 150k advertised routes. The IPv4 address space will fragment further now the price for IPv4 addresses is going up fast. Everyone with enough unused space will fractures their assignment and sell the unused pieces.

That's also your business reason. The price for IPv4 connectivity will go up. At some point a startup will not use IPv4 anymore because it will be too expensive. If you don't have IPv6 access you will not be able to use the services of that startup.

Price of an IPv4 address has doubled last year and gone from about $7.50 in 2016 to about $40 now. https://ipv4marketgroup.com/ipv4-pricing/ https://ipv4.global/reports/