We did take the tests required. We checked in online like we always do. The check in process didn't require a completed verifly. The verifly app wasn't working properly on our phones and kept erroring so we couldn't complete it in parallel. As we understood its optional anyway to speed things up, we assumed they'd do a manual check at LHR. When we got to LHR, already checked in, we went to bag drop, left luggage and went through security. The only things anyone wanted to see were the passport and boarding cards, which we printed out the night before.
When we got to the gate (Sunday 1st May) we were a bit worried as no one had asked to see our certificates (test or vax) and we were worried it would be an issue when we got to the US. So we asked the BA person at the gate whilst waiting for the flight to be called. We told her we can't get your recommended verifly app to work, what should we do, do we show you our certificates? (One certified negative lat flow from Express Tests from 3pm the day before and one certified Recovery Certificate from Online Covid Tests). She said, and I quote - "oh don't worry about it, the verifly app is no longer is use and isn't being updated so we know it doesn't currently work properly on Android. All you need to do is fill in the US attestation form here" - and she showed me a link and QR code on her iPad which we scanned and it took us to the US attestation form site (which we didn't even know about depsite research as everything had told us on the BA website etc to use verifly!).
I was a bit surprised so I double checked with her, something like, really? We don't need verifly? And she said, and again I quote, "no, it's obsolete now". I also said do you want to see our certificates? And she said no, no need, just fill in the US attestation form now before you get to the US.
So we filled it in, answering whatever it asked truthfully. I can't remember now what it says but we would have said yes we are fully vaccinated, as we are, and yes we've done negative antigen test in last 24 hours/or have a recovery cert, because we had. But you definitely weren't required to prove that on the attestation form by scanning the vaccine/test/recovery certs like you used to be on the UK passenger locator form.
Then we flew to LAX. Border control, who presumably can see your attestation linked to your passport (along with your ESTA status I presume as no one asks to see that either), then let us through with the usual why are you traveling to the US questions and did not ask to see any certificates. We flew from LAX to Maui the next day, again checking in online with a different airline, and again nobody at either end asked to see any evidence of vaccine status, or recent testing (which wouldn't have been required at that point anyway as domestic flight). We then moved around the islands and again nobody ever asked about covid vaccine status or testing.
My point is perhaps they will also relax the requirements, in the near future, like we have, because they don't seem bothered about checking/evidencing it, like the UK also stopped caring in the weeks before it dropped the testing/passenger locator requirements (I was traveling back from Europe the week before that Friday when all our requirements ended and nobody asked me anything about covid. You were still required to technically do a 2 day test as we returned on the day before requirements were dropped. I did a Radox one. None of my colleagues bothered. No one cared).