I'm thinking of making an adapter to use 1s liPo for a 2s drone like Oscar describes here:

https://oscarliang.com/combine-two-small...r-battery/

wondering if it makes sense to have two bt2.0 connectors lead to an xt30, or if the xt30 would be bottlenecked by the bt2.0 connectors?

BT2.0 support 9A continuous and 15A burst. XT30 is 30A continuous and 65A burst. You can use two BT2.0 into XT30. Make sure your wires are properly gauged.

ok great. Thanks for those specs!