RV MFGs install those check valves cause they are cheap and easy to do prior to installation of WH
Cheaper then a shutoff valve/piping/connections for valve and the labor
Winnebago and another MFG go even farther by installing check valves in Cold Inlet
I have 3 valves (cold in/Hot out/Bypass) and NO Cheap junk check valves
Yes you can do away with the check valve
Might I suggest installing a Sharkbite, Gatorbite, FlairIt shutoff valve on Hot out so If needed WH Tank can be isolated and bypassed
Just curious:
Why the replacement of that Suburban WH?