Human ships go fast

If a megacorporation wants to set up regular supply lines between Rigel and Betelgeuse, they will contract with the Tel'vari. The sentient plant-ships are excellent for low-risk interstellar travel, and the Tel'vari are so long-lived that individual ships have strong reliable track records.

The Swarm Queens of Vartax are also excellent interstellar ships, passing genetic memory between queens, and operating entire fleets through their hive intelligences, so long as they remain close.

But you need to be able to afford supply lines that take centuries for a round trip to work with them. If you're any smaller than Novacorp, those kinds of expenses will be hard to swallow, and you've got to bow to your betters, and accept whatever price they demand for a bottle of off-world Hive Liquors, or military alloys.

The humans however, have found a rather insane workaround.

Initially developed by human smugglers, they invented a method to temporarily spawn and erase a chain of black holes designed to drag a ship forward, while also distorting space along that line. These smugglers could cover the distance between Rigel and Betelgeuse in a matter of years, allowing a single captain to run multiple shipments within one lifespan.

A lifespan mind you, that is all but guaranteed to end in ruin. The early Pull Drives were known both for their speed, and their high likelihood of destroying the ship it propelled. Smugglers eventually developed a Pull Drive that had a mere 20% chance of catastrophic failure. They also began to launch their ships from specific points in solar orbit, specifically to make the orbiting wreckage easier to recover in the event of catastrophic failure.

But the smugglers made huge incomes in short times, undercutting millenia of trade monopolies.

Thinking to cut the problem at the bud, the Tel'vari began sending military fleets to the human home system, to force the human governments to crack down on smuggler operations, and to deny the smugglers a home planet if the humans resisted.

But over their vast millenia of living, the huge sentient plant-ships of the Tel'vari forgot that warfare was a job for the fast. And the entire campaign was over before the Tel'vari had made it even halfway to the Sol system. It seems the human governments had been testing Pull Drives on their military vessels.

Even though the catastrophic failure rate remained undiminished, the speed it provided made offensive strikes against them suicidal. The Swarm Queens contented themselves to improve their own system's standing defenses, and marketed themselves as the more reliable option for high-value cargo, compared to the high-risk high-reward human traders that began to dominate the starways.