Anecdata here, but Google have been constantly hiring in SRE for as long as I can remember (in London). As someone who's moving in that direction career wise I

Anecdata here, but Google have been constantly hiring in SRE for as long as I can remember (in London). As someone who's moving in that direction career wise I don't think they're any harder to hire than a good software engineer, the skillset differ somewhat, but the culture/thought process is very similar which is what you hire for.