The basic problem with the Scope-Sweep Generator method for Bode Plots, and we've used them in the past, is the lack of Vertical dB scales (linear Vertical screen resolution limited to 30~40dB range, and no dynamic V axis scaling), and the lack of any direct Phase plots. The modern DSOs under discussion do a respectable job here, some completely self-contained (built-in AWG), have dB Vertical scales (some with dynamic scaling over 100dB), direct Phase plots, and allow direct digital document recording/printing of the results.
Recall long ago doing the analog Scope-Sweep Generator Bode routines, and having to capture photos of the scope screen, and having very limited Linear vertical scale factors, then having to generate the phase plots by measuring the time delay shift between scope channels, calculating the phase shift, tabulating and hand creating a Phase plot on the Xerox scanned magnified version of the Polaroid image of the scope screen.
We'll take the DSO Bode capability over this Scope-Sweep Generator routine any day, thank you!!
Sure if one has direct access to a Network Analyzer (we did, but these were often under use by others) that's better than the Scope-Sweep Generator routine, or even the modern DSO Bode capability. However, many don't have direct access to a NA, and they tend to be very expensive, even on used market, so a DSO at hand (if available) can serve a very useful purpose here.

Been around a long long time and done just about every imaginable measurement possible, often even having to design our own test equipment because nothing was available from anyone that could do what was required measurement-wise. Must say these new DSOs are remarkable in the ability to do almost anything and everything a quality analog (Tek) scope could do, and also perform respectable measurements that other dedicated equipment was often acquired for. To add icing on the cake, the relative cost of these modern DSOs is modest, especially compared to their overall capability.
This is from an old diehard analog type, that spent 60+ years with Tek and HP equipment, and finally decided to get our own modern DSO a few years ago (long story) to play around with

Best & Happy Holidays