IMHO trying to decode data on a scope is a bit silly in the first place. A scope is for inspecting the analog characteristics of a waveform, if you want to decode protocols a logic analyzer or MSO is the appropriate instrument. Those little USB logic analyzers are so cheap now that it has never bothered me that my scope can't do serial decoding.
Which USB logic analyzers are you thinking of ?
The cheapest logic analyzer I can think of that can match the 500MSa/s rate of the SDS2104X Plus is the Saleae Logic Pro 8 at $699. It is half the price of the scope.
Granted the SDS2104X Plus needs an additional software license and a probe and the combined cost is $538, but some people prefer to have everything in one instrument and not to have to use a computer.
So it makes total sense to be frustrated at a missing feature that could be easily implemented (i.e. search)

I agree however that for low frequency work, or someone on a budget, it is possible to use a clone of the original Saleae logic up to 24MHz. But that's not 100% ethical. And then, people willing to do that might also crack the license of the MSO option for the scope, which brings the cost down to the probe only ($369) so that starts to be a meaningful difference for some people ($699 down to $369 for 500GSa/s digital capability)
Oh and I didn't get into the number of channels. A Logic Pro 16 is $999. Same number of channels than the $538 with the scope.
Do you have any other USB logic analyzer brand in mind that can achieve these specs and at a lower price ? Maybe I am missing one, not sure