I have a 2018 Trek Emonda, so far it is creak-free, but I recognise that the BB90 bottom bracket is far from infalible, but the frameset does seem very well engineered. I've read cases where owners have had a whole bike replaced by Trek with no quibbles due to creak, in one case I read the bike was 8 years old, replaced within 1 week with a much higher spec model since the equivalent was out of stock.Exactly. None of those bikes are the sort I would ride anyway, but it just goes to show how much mark-up there is on the "premium" brands, despite a lot of them being pretty much the same under the skin. Some of the pricey ones are also plagued with creaking BBs and really crap manufacturing tolerances, so it's not like you are necessarily even getting a better product for all the extra cash.
I think the new Emonda is more similar to the Tarmac than the Domane that the OP is considering. Given a choice of the Specialised or a Trek, I'd go for Trek for two reasons. Firstly the latest Emonda and Domane no longer use those potentially creaky press fit bottom brackets but the T47 threaded type instead; secondly Trek have a particularly good rep for warranty. Otherwise Hambini Performance Engineering seem to have a range of solutions to sort many of these problems - though at cost I grant you.
Having said all of that I'd also be tempted by the Merida Reacto, Ultegra and disc brake equipped for £2500, with Fulcrum wheels available from stock at the time of writing from Tredz ... and then there are those porn star looks.
I'd probably ride wondering how long the BB30 bottom bracket will last though, and eventually wish I'd bought the 2021 Emonda when it gives out!