OpenType SVG currently doesn't support blend modes, so you'd have to "flatten" those, but it does support opacity and gradients. The image above would work nicely in OpenType SVG.
The complexity of the outlines most likely impacts the file size more than color/opacity data, by the way. Gradients are quite small in footprint and can be re-used, and in the case of WOFF(2) compress really well.
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The complexity of the outlines most likely impacts the file size more than color/opacity data, by the way. Gradients are quite small in footprint and can be re-used, and in the case of WOFF(2) compress really well.