Ars technica provided the two key pieces of context here:

“Zaiger targeted Valve and Steam users for its scheme precisely because the arbitration clause in the SSA [Steam Subscriber Agreement] is ‘favorable’ to Steam users in that Valve agrees to pay the fees and costs associated with arbitration,” Valve said.

Valve said that Zaiger’s “extortive plan” was to “offer a settlement slightly less than the [arbitration] charge—$2,900 per claim or so—attempting to induce a quick resolution.”

https://arstechnica.com/tech-policy/2024/09/steam-doesnt-want-to-pay-arbitration-fees-tells-gamers-to-sue-instead/