The ultimate goal with a SaaS is to "land and expand" where you can hook somebody at a cheap point, withhold some valuable features or add hard limits somewhere, and just wait for customers to self-select: the people that use your thing more hit upgrade walls faster and upgrade further and pay you more over time.
Whether or not the ideal inital price is $49 or not, that takes time to determine, but one thing about not offering anything to the lower-end is that you only invite better competition. At $49, you don't give much room for somebody to compete with you on price and still run a profitable business. At $99, attack of the clones. Frankly, after being on HN twice in a week, I am expecting the clone Banner<Noun>s any day now.
Are you describing distribution of controlled substances having addictive properties or "Software as a Service"?
Based on your definition of "[t]he ultimate goal", can you delineate the difference?
And by having the $49 tier present, the company can advertise that their pricing "starts at $49".
Also, there are probably some people whose purchase authority is limited to $1,000/yr.
I ask because BannerBear has 3 tiers: $49, $99, $399.
It seems like if you're willing to pay $49, you'd also pay $99 ... and as such, why not just eliminate the $49 plan.
https://www.bannerbear.com/pricing/
EDIT: Why the downvotes? It's a genuine question and if you don't think so, please just comment why you don't think so to advance the conversation.