Does the latest API on classes,triggers,and components provide a performance benefit over older APIs?

Question

My thought is "no", but wanted to see if anyone had any information on this.

I would assume the versions simply control how you can interact with the features in Salesforce (ex. methods you can use, object/field access, etc).

Assuming you have a customization-heavy org, is there any performance benefit (transactional or deployment) for being at the latest API version (47 currently) versus 10-15 releases behind (ex. 32) across all your custom components (trigger, apex classes, lwc, VF pages, etc)?

Answer 1

As you've guessed, the answer is indeed "No." Compiler enhancements in "future" releases affect all "previous" API versions, thus improving overall system performance regardless of API version. The only requirement for compiler changes is that such changes may not materially affect the behavior of previous versions, unless documented in the release notes. I don't have a specific function in mind that was affected this way, but it has happened in the past; this happens when salesforce.com fixes a critical bug that affected system behavior. These changes are kept to a minimum to make sure that Hammer Tests do not fail.