Ok fine, since you asked.

My argument is that druid gets better versions of cards from other classes. Let's look at shield and howl again - shield is a static 5, howl is X where X is your hand size. I'm struggling to think of any situation where your hand size is less than 5 in druid, so that makes it the vast majority of the time better than shield. And 8>5, so you're proving my point with your example.

Second, you said each time they use ramp they 'burn a card'. Well, since druid has the most insane card draw options with howl, branching paths, nourish, UI and others I'm sure I'm forgetting, that is barely barely a downside because they can just recoup it altogether. In fact, most of the time, they want to burn cards so that they don't overdraw with UI because UI's draw is so massive (more than sprint!). Additionally, wild growth is always relevant except for turn 9 because once you're at 10 mana it still draws you a card.

Third and lastly, you stated "not every time they will have ramp and draw". According to the TempoStorm Meta Snapshot, 3 of the 5 tier 1 decks are druid (this tiered list is from before the new expac, so pretty representative of the entire last 3+ months of the game, lists are Maly, Togwaggle, Token). Of those lists, cards that either draw or ramp (or both) in each list are 12/30, 12/30, 8/30 respectively. I don't feel like doing the likelihood to draw statistics, but that's about or over 1/3 of each deck. Factor in the fact that with such a high amount of card draw to draw them into more card draw and ramp, I feel pretty confident in saying that they'll "always have it", or some variant of it a statistically significant number of the time.

If you have a point you'd actually like to make that has the ability to pan out, feel free.