People would click all of Best Value, Fastest and Cheapest to try and ensure they hadn't missed any results.
Personally I clicked between those to assess their value rather than to see if anything was missed. It was more a case of "look at the cheap ones, are the cheap options cheap enough for me to pick them even if inconvenient", then "look at the fast ones, are the fast options fast enough to make them worth a higher price or is one of them also unusually cheap"?
You can still do that from the list there is now but the very large number of them makes it fairly challenging on longer journeys, with lots of "noise" (midpriced ones with lots of changes, usually - almost nobody would choose those) coming up too.
I didn't particularly like the Timeline, but I do see sense in a curated view as the old version has even if in addition to a full view.
It is of course very challenging to present this sort of data, but I do wonder if there's a better option somewhere between the two.
To give you one example for a journey I did actually purchase, looking at Hull to Bletchley on 1st March, we are given the Hull Trains service at 1633 (direct to Kings Cross), over to Euston then WMT arriving 2030 for £64.48, that's the one I actually picked (well, I didn't quite, I only booked it to Kings Cross so I can use a flexible ticket for the last bit, but it's a good example here

). We are also given a Northern service to Doncaster at 1627 connecting onto the same Hull Trains service, introducing a massive risk and a faffy added change into the journey to save...76 pence Sterling.
Unless someone was deliberately looking to purchase an itinerary that would have a high chance of resulting in a chunk of Delay Repay, nobody in their right mind would do that, and selling it to a random member of the public would probably result in dissatisfaction with the railway when the connection was inevitably cancelled or very tight. I'm really not sure that one should be shown at all, it's just noise. And I find the new Trainsplit shows an awful lot of this kind of stuff which just makes finding the good stuff harder as it makes the display really cluttered.