I'm not sure you can compress vector graphics so much. I think vectors are allready that small they can be, or at least almost so small that they don't compress. Or if they are compressed, something will be gone, maybe distorted or somehow regenerated differently.
If one gets too big file sizes with vector graphic pdfs maybe one needs to go and edit the attributes in PLN, like fills or line types or so.
It's the pictures (png, tiff, jpg) which can be further compressed within pdfs.
I do own Affinity suite for both Mac and PC, but because I am mostly on Mac, I use quartz filters for compressing the pdfs containing compressable pictures. I can have the filters saved within export dialogue in MacOS Preview app.
Quartz filters are made in Quartz Composer app (included in OS installation). That's what several other forum members have used too, and are using still I can read from forum posts.
I might be wrong though, maybe there is bloat in pdf vector graphics too that can be compressed. I haven't been much succesfull either with that though.
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