Trials of Osiris will be much more accessible once it arrives to Destiny 2 but the more hardcore fans might not be happy with all the changes.
Trials of Osiris represent the pinnacle of Destiny 2 PvP and when someone pops up in Crucible wearing an armour set and brandishing weapons only available here, you know they are the real deal, for the most part. One of the reasons for that was Passages being merciless on the players' economy and time due to the cost and all those resets. Both of these aspects will change, to the joy of the majority of the players but chagrin of those enjoyed some semblance of Trials prestige.
Changes to the Passages purchased from Saint-14 will be the driving factor here as they will now be much cheaper and even more forgiving. They will no longer count your losses, meaning you will no longer need to reset the passage every few matches and the value of Passage of Mercy will be diminished.
They will still track up to seven victories from what you can see in the UI but in the background, they will go as far as 20 victories. The reason you see up to seven is to be aware of your reward scaling since reaching three, five or seven victories will increase your rewards at the end of a match. On top of that, Passages are now account wide so you don't have to buy them separately on all three characters.
If all of these changes are not enough to entice you to give Trials a go, you might want to check out the two weekly challenges that will appear, offering rewards for 50 rounds won or seven matches won on a given weekend.