As the title says. This is a warning based on personal experience. I was gearing up to solo bonemass. Fully kitted I portaled in to the location and was swiftly murdered by pure folly by an abomination, a two-star Draugr and some leeches. Rather than rage quitting I quit the game, enabled console commands and resumed my game. The intention was to simply retrieve my belongings, which I did.
Upon defeating bonemass however, I noticed that I no longer had any sense of enjoyment through progression and success.. I've since left the game and turned to other things. I've had a great time and I love the game. Looking forward to content and development.
Hopefully I'll return in a good while..
TL;DR: Don't enable cheats, they ruin the experience. All progress up until that point seems meaningful, but all subsequent play seems less so..
Source: https://www.reddit.com/r/valheim/comments/shrp26/warning_debugmodedevcommands_may_ruin_experience/