A bencher isn't actually dating you — you're a reserve kept warm for possible future call-up. A cushioner is already in a relationship and keeps you as a side option in case it ends.
Side by side
Aspect
Benching
Cushioning
Their status
Single / dating around
Already partnered
You are
A reserve option
A backup cushion
Their goal
Keep you on call
Soften a possible breakup
Progress
Never activated
Hidden on the side
What each one means
Benching
Benching is keeping someone on the sidelines as a low-priority option — enough texts, likes and vague plans to keep them interested, but never advancing to a real relationship, while you keep other prospects in play. Outside dating, benching is the plainer thing the slang borrows from: pulling someone out of active play on a team.
Cushioning is staying in a committed relationship while quietly keeping one or more romantic "cushions" on the side — flirty texts, kept-warm backups — as a safety net in case the main relationship ends.