No. Onramp is a custody solution, not a custodian. Bitcoin in a Multi-Institution Custody vault is protected by three independent institutions (Onramp, BitGo, and CoinCover for individuals and IRAs), and it takes two of the three to move it.
Bitcoin in your Trade wallet, where purchases settle if you don't send them to a vault, is held at BitGo, a qualified custodian. Onramp holds $1B+ in bitcoin under Multi-Institution Custody.