Los, Target Required, Actions not executing

For some time the above issues have been present in GW2. These issues noticeably began after the update to Line of Sight (los) which ruined the traversal for thieves and the mesmer blink. So much that you can be los from a shadow step on what is seemingly flat terrain or a a few steps to an elevated hight. The biggest issue with this however is when you have an enemy targeted and there is no noticeable terrain or objects to cause los and yet you are obstructed from view and cannot damage the target. This issue has been going on for years.Another similar issue to los is the Target Required error when you have a target acquired/selected and no actions are able to be used. This issue has been noticed recently.One of my bigger issues with the current state of the game is this one. Actions that simply do not execute when being activated. The symbol on the skill bar will depress but ultimately not execute. This issue has been going on for a longtime.With the coming expansion. living world and gem store updates, playability has seemingly been shelved altogether. I'd like for this to change as the game is actually suffering from this. Although this is the least performing title in the NCSOFT catalogue I do not believe it should be neglected on its technicals in favor of pushing monetary incentives to the playerbase.

Is LOS dependent on character's size? I guess that it is not, but who knows?

A couple of us got the LoS problem when trying to use distance skills on the supervisor in the SEC in one of the borderlands. We were just beyond melee range. There wasn't even a blade of grass in the way.