sure, it can stay until level 5 at the latest.
you cannot make a key class feature, spend class resources to improve it, give worse capstone feature in the game keyed to it and have Concentration on it, preventing usage of lot's of spells.
I bet I can...
not that it might be my best idea. But on the other hand, my ranger fantasy is using spells mainly for exploration and maybe healing. I never saw ranger as the buff or debuff class.
So if all the ranger uses in combat is hunter's mark, i am happy enough if they can make use of their spells outtside combat.
Making hunter's mark a concentration class feature is a forceful way of achieving that.
I mean how many people are there that don't want the ranger to cast any spell at all.
That does not mean that the capstone is more than dissatisfying.
But if the ranger spell list and the spells wothing are improved and the bonus action economy is fixed, the ranger is in a great enough spot. Especially when you remember they now have also ritual casting for alarm, beast sense, animal messenger etc.
The 2014 ranger class was never bad in actual play. They had utility, they had enough damage, especially as a bow user. It just felt clunky due to action economy, and their spellcasting was too limited so a lot of cool spells were never used. Even the tasha fixes (favoured foe giving bad hunter's mark as ability) did not sit totally right.
So even though I understand your disappointment, I bet the class will play perfectly fine and way better than 2014 ranger.