To me, meaningful choice means something you can actively decide upon to determine which tactical benefits you want to produce.

Like if you could choose between Adloquium for less healing but stronger defenses, or Physick for more healing but no long-term defensive effects. Or if you could choose between using Sacred Soil to strengthen the party’s defenses or Shadowflare to lower the enemy’s offense. Or maybe even something like, Biolysis and Miasma being mutually exclusive DoTs with two different additional effects. That’s not how they work now of course, just examples.

Furthermore I think buffing/debuffing is more likely to result in ‘meaningful’ decision making because it’s going to be context dependant. DPS’ing kinda can’t be context dependant by definition, because it’s practically impossible to ever make a scenario where dps’ing isn’t immediately the ‘best’ answer. Plus, buffing/debuffs needs limitations and restrictions for balance, and those limitations, possible exclusivities, resource managements, etc, can increase the amount of decisions healers get to make without falling as far into the ‘just always use it’ that dps abilities can fall into