well as long as you don't go over there weight ratings and replace and REMOVE stand from tree as per MFG's recommendations there super safe, as per NOT breaking or coming off tree/
they use same like straps to hold cargo down on trailers and such, in tens of thousands of lbs( they make straps in all sizes more or less, just weight rated per application)
the flaws with straps , is honestly, that folks tend to LEAVE them on tree's for too long, or can get UV damaged or critter's can chew on them(never had it happen but have seen it)
MOST all tree stand makers, tell you NOT to leave stand on tree for more than like a week or so at a time, due to the tree is always growing and can apply ton's of tension, to things, and cause a failure
very few hunters remove there stands as per MFG"s instructions
most I think leave up all season??
ME< I never left lime up for more than 2-3 weeks, and I always added a second strap as a safety net of sorts, which I think is common practice among many hunters
but just cause there straps and not chains, or cable, doens't mean there weak, just have to live with the steps you need to follow to be sure there safe and used correctly!