It is not harder, it is different. They just ask more system topics, while focusing less on coding. There is, however, a catch. If you get hired as a SRE-SWE, you can easily switch to a regular SWE. If you get hired as a SRE-SE, you may have to reinterview to change your job ladder. SE is okay, but you clearly have more possibilities as a SWE.
SRE-SWE and SRE-SE on the same team will have exactly the same expectation given the same level.
Depending on the project you work on, you might have a code-heavy project that requires you to work closely with the SWE team, or an operability-heavy project that doesn't have much coding.
