Since version 2.90 of the Sentinel-1 SAR processor (then since 13 March 2018), the GRD borders are cleaned from “no values” pixels.
Then the “remove-grd-border-noise” should do nothing on recent products: the edges may contain “no-values” that are kept.
For the old products the edges contained pixels with small invalid values that were flaged as “no-values” by this process.