I think you should read your economy books once more.
1. In general monopoly doesn't mean exorbitant prices.
I have just painted a picture. It the only picture painted by me in the whole world. I have a monopoly for it. But noone wanna pay even 1 dollar for it.
You can buy an imbued Daiymo helm for 8m. In spite of monopoly it is difficult to sell it.
But there are monopolies which, if left untouched, may harm the economy of a society (and sometimes harm very much...), and that is why most countries do have a powerfull anti-trust agency, to control and take care of that in the interest of competition and of the overall economy of a country.
2. Equal probability doesn't mean equal possibility.
An old reach player have the same probability to farm a high-end PvP ring as me. But this probability is close to zero. But a reach player can pay few billions to a luckier (one per million) who found the ring. So he/she can get such ring without problems. And it's practically unreal for me to get such ring.
In D3 was the similar situation. Players who started to play from the first day farmed good items at Inferno difficulty (pretty common in Inferno and very rare in Hell), sold them per 10m (to beginners who weren't strong enough to farm Inferno) and bought extremely rare high-end items per 100m (not much players were able to pay 100m) = 1 to 10 ratio with pretty common items. Players who started to play two months later farmed very rare very-good items at Inferno, sold them per 1m (most of player already were able to farm Inferno) and bought high-end items per 500m = 1 to 500 ratio with very rate items.
Equal probability doesn't mean equal possibility because, unfortunately, wealth becomes a factor and thus, some players who can afford it, jump to the better items by purchasing them rather then hunting for them which requires more time. Yet, my problem was not much with items which still spawn, like slither for example, I do not have a problem in slither costing 80 millions UO gold because it still spawns and so, those players who cannot or do not want to spend this gold for one, can still go and hunt for it.
My problem was with imbued artifacts which only a few players have been able to while the vast majority have not been able to. This creates a divide in between players and a monopoly of imbued artifacts by a few players where many other players do not have any longer the possibility to do the same thing.
As in regards what artifacts may have been imbued, I would imagine that those that have been imbued have, for the most part, been the most usefull and with the most interesting properties on them, not the junk ones....
3. If the developers deleted items than players have stopped playing.
It would be pretty fair PvP except you were the only player on the shard. Very few people like the situation when he/she spend few month to farm enough gold to buy an item just to see it disappear few days later.
Well, there is always the possibility to simply "revert" an imbued artifact to just what the artifact was, prior to imbuing. Just remove the "imbuing"..... No deletion of items, just correct a wrong.
4. There is a 14 or 15 years veteran reward that allow you to transfer character between shards.
Younger players must pay ~100m for two transfer tokens if they want to buy something on another shard.
I see no difference as with your example of players paying gold, more gold that other players, to buy the items they want. Eventually all players, if their active account time comes of age, will be able to have their Shard Shields. So, this is equal opportunity to any and all players, NO DIFFERENCES WHATSOEVER.
Furthermore, those who want to transfer can do it at a small fee, AND have the advantage to transfer up to 5 packies along with, while the Shard Shields do not allow for any packie. So, I see no problem here much.
1. (continued)
There are some artifacts (lt-sash, int boots, ...) that don't drop nowdays.
The developers are not so stupid to ruin PvP. All old artifacts that very suitable in PvP have replicas.
And that is why we now have [replica] items and the Minax items, so that any and all players have their ability to get the same items as other players thus eliminating the difference between players which was so much hurting fighting and PvP in Ultima Online.
I think we have a great Developing Team in Ultima Online with a very good long term vision for the design of the game and they are implementing the good changes for the game. I just think they made a mistake not reverting the imbued artifacts to regular artifacts as they were prior to being imbued before it was stopped.