This reverts commit e0b2174.

This reverts commit e0b2174.

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**Context:** Due to non-negligible performance impacts, PR #6933 is to
be reverted. Flattening each wire contents introduced overheads between
5-60% in benchmarking, and will be reassessed for support in a follow-up
release.

**Description of the Change:** As above.

**Benefits:** Restores lost performance.

**Possible Drawbacks:** Reintroduces incompatibility for nesting of
wires

**Related GitHub Issues:**
[sc-87017]