An MP is paid a salary. Whether they attend debates, or speak, in them or not is a matter for their party in the House, their local party (who may deselect them) and their electorate. Those bodies may find the work the MP does satisfactory; it is not essential that the MP speak in the House, nor that the MP attend debates unless the subject of an appropriate whip.
Peers are paid a daily rate for attending the Chamber or Parliamentary Committees. they have to attend to get paid. If it requires an Act to remove one, all that is necessary is for a Bill to be drawn up every so often listing the various offenders, present it in the Lords, and then let it go through the Commons ,to Assent ,on the nod. In the meantime, the peer may be suspended (as does happen now). It is a grave defect that a peer cannot be removed for "bringing disgrace on Parliament and this House".