I think an exception should be argued for DMsGuild Community Creator products, since not everything needs to be boycotted to achieve the objective of grabbing Hasbro's attention and focusing that attention on the WotC execs responsible for managing the DnD brand and related licenses.
To financially attack or harass small developers who might need the income to supplement their living in the current bad economy even though they have nothing to do with decisions regarding the OGL is like throwing the baby out with the bath water and potentially adds hypocrisy to the motivations behind the boycotting.
DMsGuild creators are contractually bound to keep their stuff on DMsGuild so they can't move themselves to a new store.
Many DMsGuild projects, especially setting books, can not be published under the OGL (A reminder that the OGL and DMsGuild are separate licenses).
Many DMsGuild projects in the works as such can not be transferred to other systems or licenses.
To boycott DND Beyond, toys, cards, and 1st party materials is already enough to make a noticeable change to WotC's bottom line without also attacking the community creators on DMsGuild.
Someone on Reddit suggested opening up a Patreon or the like, but building a following for that to compensate would take a lot of time, work, and luck as not everybody is on those sites nor would be willing to help out (at least not enough).
Starting over on another site likewise also takes a lot of time, work, and luck, which obviously can't be done overnight and may not work out at all.
The goal should not be to destroy WotC or DnD out of spite, because that's unrealistic and insane. The goal should be to pressure change in the culture at WotC, and it does not require hurting the small developers on DMsGuild.
Please don't step on the little guys while claiming it's for their own good.