The guidance is this: if breastfeeding without a cover will materially degrade the experience of whatever is communally being experienced, then use a cover. At church (tight quarters talking about Jesus) ≠ at the park (strong ability to avoid).
Not too dissimilar from people using a speaker phone on public transit. If you need to take a call, that is fine, but you don't have to make both sides of the convo everybody's bidness.
Richard (npub1fvz…tzuw)