As TJagain says. What do you class as value?
Quite. When I bought my Sonder Transmitter frame it was £300 and a bargain at that price because it rides far, far better than it has any right to. It’s now £100 more and still arguably ‘good value’ for the same reason, but slightly less ‘good value’ than before.
I honestly have no idea if the full builds represent value or not because I generally buy a frame and add bits old and new.
If you’re comparing build kits, then things get more complex. Personally I don’t really care about drivetrains as long as they’re functional, but decent suspension components and wheels that don’t weigh a ton and/or self destruct are important and make far more difference to ride feel. I’d rather have, say, a Pike up front and a Deore drive set-up and brakes than a budget fork an XT or XTR let alone some SRAM drivetrain with a £300 20-speed, dinner plate cassette. When’s the last time you thought your cranks were lacking?
Anyway, ‘value’ is basically a moving target and relative to performance, durability and expectation as much as RRP. What might be value for one person could be extravagance to someone else and vice versa.