If Apple's still selling it, they'll almost certainly support it at least as long as an above-average Android manufacturer.
The current iOS supports things back to iPhone 11 and the SE2, so you can expect the SE3 and iPhone 13 to get at least two more years of support (no real guarantees, but they're still selling new stock of both, and they have a reputation to protect).
The current iOS supports things back to iPhone 11 and the SE2, so you can expect the SE3 and iPhone 13 to get at least two more years of support (no real guarantees, but they're still selling new stock of both, and they have a reputation to protect).