There are lots of different views about the goals of antitrust law and policy, but few (if any) are hostile to business. Khan is pro-business but also, broadly speaking, pro-dispersion of economic power within the economy. That means having fewer 'gatekeeper' firms which exercise power over key economic bottlenecks, and at the same time, a greater focus on helping smaller and medium sized businesses succeed.

For a concrete reference regarding small business, see this recent speech of hers [1,2].

[1] https://www.ftc.gov/system/files/ftc_gov/pdf/remarks-chair-k... [2] https://www.ftc.gov/news-events/news/speeches/remarks-chair-...