Depends how many IPs you're using. If you're using 10, who cares; if you're using 100, I dunno. If it's 1,000 or more, that's real money you probably shouldn't be pissing away. (OTOH, a lot of cloud spend is pissing away money, so what's another $45k/year)
But if you have 100 backend servers that mostly communicate on the internal network/VPC and need their IPv4 mostly for updates, it seems easy to justify standing up a proxy and reconfiguring your template. At least if your engineers aren't in Silicon Valley and thus don't cost you $400/h.
you don't have to break even on implementation. you will get billed every single year, so if you can have two dudes solve this in 3 months, you can break even in 3 years and every year after that you saved money
In most companies that would worry me. That there isn’t anything more impactful to work on than a project that breaks even in 3 years likely is over staffed and I’m likely on the chopping block when things turn south.