Well for marketing and sales your bigger competitor is already doing the work of showing companies that they want the functionality at all, and the cheaper competitor's sales and marketing pitch can be: we are much cheaper.

This is pretty much what blacksmith.sh does -- GitHub Actions but it's on faster and cheaper hardware. I'm sure they spend non-trivial amounts on marketing but "X but much cheaper" doesn't sound like a difficult sale.

(edit) And the design, sadly, can be as simple as "rip-off bigger competitor" -- of course if one day you are the big competitor because you "won" in the market, you'll need to invest in design, but by then I guess you'll have the money?

they dont, which is why these companies are going to get smoked. a small team of people will compete with atlassian head on. the whole saas business model is under threat