This is almost never the case, and if it were the case would be limited to Blu-ray or certain pay-per-view on cable boxes. Otherwise, things like DVD players, or BD players still play almost all of their content just fine over component.
Worth saying (and asking) - Why not run HDMI to the projector and have you tested this connection at all? The projector has a HDCP compliant DVI input, which should be able to accept 720p and 1080i video over it. Run an HDMI cable between your sources and the projector and use a HDMI to DVI adapter and call it a day! Should work well and takes you into the 21st century.