Otherwise you're a jumped-up contractor with a hobby project. And you're not going to be taken seriously as a business partner.
I learned this the hard way in the early 00s. It's one of the fundamental marketing elements in B2B, and it has nothing to do with the quality of the product, its features, its ability to solve problems for a convincing price, and anything rational.
You can even say that anything above the very lowest levels of corporate B2B marketing - excluding the trades and very small mom & pop SMEs, who are a separate market - is about projecting business charisma and potency, not so much about solving actual problems with any efficiency or effectiveness, and certainly not about solving them at an affordable cost.
It's entirely tribal. And if you're a one-person shop you're an outsider - effectively just a potential employee or remote temp - and not part of the tribe.
IMO no amount of marketing and validation can overcome this bias in B2B. You're just not going to be considered a worthy equal, no matter how you spin it, or how good your offering is.