I have one IP address for my nameserver, my web server, mail server, ftp server. I use SNI SSL so that my hosted websites have different SSL certificates behind one IP. I use a centralized firewall to protect UDP, TCP, ICMP traffic.
Are there still benefits to use several IP addresses today?
Sure there is. If you had more than one DNS, FTP, mail, etc... servers you may need additional IPs to distinguish between them. Also, if you had multiple links (for various reasons), it could be required to access those same servers.
Today, many IPs (public IPs if you mean so) are used to balance the traffic dirrectyl on internet.
There are not other priviledges than having many of them to distribute the load. Or to have server availability in case one of connections goes wrong. As providers di-per-se will never give you more than one IP per physical link.
In some infrastructures it is beneficial to have a dedicated physical link for ssh. That way you will still be able to access your server when you are the victim of a DDOS attack.
When using virtualization it is quite common to give each virtual host its own IP using bridges which means that one physical interface is in charge of potentially many IPs.