Will 2020 Intel MacBook Air run macOS Tahoe?

It won't according to the following from OS - macOS - Apple

macOS 26 is compatible with these devices.

Explore Mac

• MacBook Air with Apple silicon (2020 and later)
• MacBook Pro with Apple silicon (2020 and later)
• MacBook Pro
• (16‑inch, 2019)
• MacBook Pro
• (13‑inch, 2020, Four Thunderbolt 3 ports)
• iMac (2020 and later)
• Mac mini (2020 and later)
• Mac Studio (2022 and later)
• Mac Pro (2019 and later)

There are a few Intel-based Macs that are in line to get Tahoe.

• MacBook Pro (16‑inch, 2019)
• MacBook Pro (13‑inch, 2020, Four Thunderbolt 3 ports)
• iMac (Retina 5K, 27-inch, 2020)
• Mac Pro (2019)

No Intel-based MacBook Airs, Mac minis, 21.5" iMacs, or iMac Pros seem to have made the cut.

The

• MacBook Pro (15-inch, 2019)
• MacBook Pro (13-inch, 2020, Two Thunderbolt 3 ports)

didn't make the cut either. The low-end 13" model used older Intel processors than the high-end 13" one, which might explain why it's going to be out of luck.

Even the Intel-based Macs that will get Tahoe won't be getting Apple Intelligence.