Here are the numbers with one of the internal tsbuildinfo
4de704d Only emit compiler options that affect

04/15/2021  01:26 PM           670,576 infoNew.json
04/15/2021  01:26 PM         1,023,762 infoOriginal.json

a422f9e: Dont emit affectsGlobalScope if its not true

04/15/2021  01:38 PM           612,256 infoNew.json
04/15/2021  01:38 PM         1,023,762 infoOriginal.json

658587d: FileInfo is encoded as string if FileInfo.version === FileInfo.signature && !FileInfo.affectsGlobalScope, otherwise property signature is encoded as false if it was undefined, undefined if FileInfo.version === FileInfo.signature and actual signature otherwise

04/15/2021  03:47 PM           410,798 infoNew.json
04/15/2021  03:47 PM         1,023,762 infoOriginal.json