Have 1000+ SFPs running and maybe replace 1 a year (I don't even remember the last failure that wasn't a DoA). We don't run SW anywhere near the max optic length so any power loss is unlikely to cause us issues so not something I monitor. ISL LW is another story but that's normally down to loss on the fiber and the SFP is typically fine after clean or repatch.
We did see more failures in the past but resent years have been good with the ones supplied by HPE, Brocade or QLogic (probably since 8Gb gen).