Given postal votes are a thing, and have been for many years (at least for UK/AU/NZ), is there still such stringent requirements on making it difficult/impossib

Given postal votes are a thing, and have been for many years (at least for UK/AU/NZ), is there still such stringent requirements on making it difficult/impossible to buy/coerce votes? Since both can be done using postal votes already. Does this then open up more digital options? Eg app based voting where your vote is published along with everyone elses but in anonymised form, so everyone can independently verify the totals. By anonymised I mean the app displays a random “vote reference ID” that you could check in the final published ledger to see your vote was included, and was recorded correctly.