That’s a shortcoming of the GPL: it doesn’t consider interactions over the network “distribution”. It’s the reason the AGPL exists. IMHO, GPL software that could be expected to run in SaaS form should be AGPL.
It's also worth noting that GPL become more accepted in the corporate world because SaaSS defanged it. AGPL is toxic to companies now, but when everyone was releasing desktop software, GPL was treated the same way.
