The standard B2B argument for a long form is that it filters out tyre-kickers and gives sales what they need. The standard counter is that every field loses some real buyers too. Both are true, and the resolution is to ask only for what changes what happens next. If the next step is a call, you need a name, a work email and perhaps one qualifying question. Company size, role and phone number can be asked on the call, or enriched from the email domain.
The one qualifying question is worth keeping when it genuinely routes the lead: team size when pricing depends on it, current tool when the pitch changes with it. Asking because the CRM has a field for it is not a reason. Make the button say what the visitor is getting, name the person or team who will respond, and state when, in hours or days, not "shortly."
If lead quality is poor, the fix is usually in the page above the form. A page that is specific about who it is for and what it replaces self-selects its audience before anyone types.
For the field-by-field version of this argument, read our guide on how to reduce form friction and apply it to the demo form specifically.