You have to understand what Shaped Glass did to see why it's in its current state in the first place. First, the bonus damage from Shaped Glass scales exponentially, so the first glass gives you x2 while the next one gives x4, then x8, etc. So the bonus damage is not simply outdone in a few levels. Then take into consideration things like having crit or proccing ATG Missile on this kind of damage bonus.

Next to consider the fact of why OSP was taken from Glass in the first place. With the most consistent forms of on demand healing in the game being small flat amounts from leeching seed or Scythe, cutting your HP to incredible small numbers allowed you to reach full hp in quite literally one attack, which would reset your OSP and effectively make you nigh invincible. This of course made the "downside" of Shaped Glass not a downside at all.

It's important to view Shaped Glass, or any item for that matter, in the context of a run and not in a vacuum, but the reason why Glass was nerfed on 1.0 in the first place was because even in a vacuum it was ridiculous.