What benefit would Red Hat (or any other large Linux company) get from buying SoftMaker and releasing its software Open Source?
Remember that this is essentially what happened with OpenOffice, so there is no guarantee that you'll see a community grow around it any faster. It probably has similar issues of fragile build systems and third party proprietary code to deal with, so it would take a while before outside developers could even get started.
A company like Red Hat would also need to weigh this effort and risk against working on OpenOffice or a derived product like go-oo (which they might if copyright assignment is a problem).
So while it might be nice to have another free office suite, I wouldn't hold my breath waiting for this to happen.