Aren't supports the reason why ADC's win their lane? or Why their team survive a team fight? Sometimes it's that shield or heal or tanking a dmg when you are not even a tank that aid in the enemy defeat. I think it goes unnotice because more ppl seem to look at dmg done rather dmg mitigated, shield or healed. ADC's do self heal with lifesteal but much times the support helps them sustain or if it's a tank support, they help by taking some dmg and all times support also deal dmg to the adc's target. I think it's just that supports don't get much appreciation for their good works and too much harsh criticism for their misteps. Thus, being a support does not seem rewarding.
I think Jg'ers also experience this but this is about supports and not jg'ers.
But support to me is very important as any other role. Just that supports get overlooked.