I'm not sure how that comment holds given what they've outlined. For the 6 month ending in 2019 they had roughly 75k
paying customers. Now the interesting part, to me, is that only 408 of them are spending over $100k in annualized billings. Given that they have some runway to expand into organizations who are down a path of transition to cloud. In the S-1 they reference a lot of "band-aid" box vendors (Juniper, Checkpoint, Cisco, Palo Alto Networks, Fireeye, etc) and so they seem to be positioning themselves squarely in the security space in competition for those budgetary dollars. I think this is the right play for them, especially because as cloud offerings continue to blur lines into hybrid architectures Cloudflare sits in a very nice position with CDN, security, VPN, services (DNS), etc. And security budgets are still flush.
But back to your comment... Given 408 customers probably generated the majority of the $100M GP over the first six months of the CY and they have another 74k and change customers they've landed and have potential expand opportunities with, I'm not so sure there's no revenue there to be had.
Now that being said I think the stock will likely float to ridiculous overvaluation at IPO and all the talking heads will argue how those "band-aid" vendors have staying power through brand loyalty and proven models... But, I personally, think CloudFlare will be around as a leader in this space for a long time, especially if they continue to keep playing their cards as they have.