In the past, Google has taken extreme action by banning all sites on an specific host and even on a specific sub domain. Back in the day, SEOs wanted their own IPs and 10+ years ago Google agreed but more recent advice from Google said IP addresses don't matter much these days at all.
Truth is, most SEOs I know, don't worry about securing their clients a dedicated IP for their site. In fact, most large and highly ranked sites are served over CDNs like Amazon, CloudFront, Google, Microsoft and other platforms.
Google's John Mueller was asked if it was safe to host your site on a CDN after one SEO said he stays away from them in fear of getting on an IP range that is spammed too heavily. John said that it isn't a problem these days for the most part. He has never seen Google ban all the sites on a real CDN.
John said at the 1 hour and 1 minute mark "for the most part I don't think you'd have any problems using a CDN." Here is what he said:
For the most part I don't think you'd have any problems using a CDN.
So I haven't personally seen any site that had any problems with using a common CDN where there lots of spammy sites.
Yeah I wouldn't see that (Amazon, CloudFront, etc) as being a problem.
So usually the the same IP problem is really a situation where we're talking about like ten thousands of kind of really spammy websites on one IP address and then you have like you're one normal website on there as well. Where maybe someone from the webspam team would say well this whole server is just pure spam, we're just going to like treat the whole servers being pure spam. But that's like a real exceptional situation. I haven't seen any false positives in that regard. But if you're looking at a common CDN, then none of that really applies because you have it this kind of natural mix of like some good some bad sites on the same CDN.
He also added that you don't really need unique IP addresses these days. The question was "So your’e basically saying but in 2016 2017 unique IPs are not even needed anymore?" John responded, "for the most part you don't really need that."
Here is the video embed:
Forum discussion at Google+.