The stated purpose of MakeMKV is to put the contents of bluRay discs and standard DVDs (not even HD-DVDs any longer).
That being the case, I'd suggest that if you have a reasonably powerful system, it would only take about 10 minutes or less to load your .M2TS file into tsMuxeR and have it converted to a standard BluRay "package"...
The fantastic thing about makemkv is that it can create a MKV file from a BD/DVD source at near the speed it is read from the source. It does not make temporary files and then remux them like every other tool or package of tools out there does.
Creating a blu-ray to then use makemkv is making it a two step process, which for most of us it already was (using tsmuxer to demux the m2ts streams we want, and then mkvmerge to join them together).