MacBook Air 13 2020 stuck at 1% battery after years of non-usage

Most likely, yes. The biggest drawback of rechargeable lithium batteries, not just those used in portable Macs, is that if left will little or no charge, for long periods of time, they "lose" their ability to be charged.

Before you commit to a replacement, you could try a couple of quick checks: use the original Apple charger and cable (or a known-good equivalent), reset the SMC (on an Intel MacBook Air 2020, that means shutting down, holding Shift + Control + Option + power for 10 seconds, then releasing), and see if macOS’s battery status changes. You can also check About This Mac → System Report → Power to see the cycle count and battery health. If it says Service Recommended or the cycle count is extremely low but capacity is near zero, that’s your confirmation it needs a new battery.

Assuming the Mac will boot up, try resetting the SMC. Also try leaving it plugged in for 24 hours (with a power adapter that provides at least 30 W and that you've confirmed works with other devices).

SMC reset and a few other steps are described here:

If your Mac battery won’t charge - Apple

Desktop computers have power capacitors in the DC power supplies to smooth out the delivered power. Portable computers use the battery capacity to smooth out power.

When you leave it disconnected for a long time, the battery can act as a Drain rather than a Source of power. So reviving it can be a multi-step process with no guarantee of success.

Conventional wisdom is that it may only trickle-charge until the battery power level gets up to a certain level. So the previous suggestions to charge it least all night long may get it trickle-charged enough that the charging logic can actually begin to work.

Then AFTER that overnight pre-charge followed by an SMC reset, it might be able to begin a real charge cycle.