.255 addresses still not usable after all these years?

I remember back in the day of old hardware and operating systems we'd intentionally avoid using .255 IP addresses for anything even when the netmask on our side would have made it fine, so I just thought I'd try it out for kicks today. From two of four ISP's it worked fine, from Verizon FIOS and Road Runner commercial, it didn't. So I guess that old problem still lingers? David