There's also some innate complications with the nature of a company adopting an open source tool. it's classic 'build vs buy', so if a company is investing in engineers building their own in-house solutions on top of open source tools, the additional cost of licensing support/additional tools doesn't really make sense. so there's immediate friction to monetize open source users.
on the other hand, SaaS products are optimized to sell to business groups who want the hard parts taken care of for them and they perceive value in saving time/money thanks to the SaaS product. I've seen both situations (monetizing open source versus monetizing a SaaS product) first hand, and it's clear that open source companies can be at a bit of a disadvantage. If they DO monetize their users, it's usually via their own SaaS offering to augment the open source tool.
on the other hand, SaaS products are optimized to sell to business groups who want the hard parts taken care of for them and they perceive value in saving time/money thanks to the SaaS product. I've seen both situations (monetizing open source versus monetizing a SaaS product) first hand, and it's clear that open source companies can be at a bit of a disadvantage. If they DO monetize their users, it's usually via their own SaaS offering to augment the open source tool.