Is Ryze crowding out Singed?

In my last ranked game, I opted to play Singed while someone on my team recommended Ryze. We lost, due to poor teamfighting on our part, by the way.

But anyway, why would you pick Singed over Ryze? They both have the same niche, being a tanky AP top who works really efficiently with mana items and does significant damage over time, but I can't think of many reasons to pick Singed over Ryze. Ryze has a MUCH stronger lane phase, seeing as how he is ranged, his damage output is better at all stages of the game (Singed's MIGHT be higher, maybe, if he goes rylais/liandries and is hitting all 5 members of the enemy team in a teamfight, but then, you could make the argument about Ryze's ult doing aoe damage too, right?), but Ryze's damage is likely to be more important because he can use his to eliminate the enemy ADC on his own, while Singed is too busy being shut down by a Banshee's Veil. Both are really tanky late game too, Singed is obviously tankier, but it might be closer than you think in terms of survivability due to the Spellvamp from Ryze's ultimate and his ability to kite.

At first I thought Singed has better CC than Ryze, but I think it might even be closer than you would think. His Mega Adhesive is potentially useless if placement is whiffed, or the fight changes location, and while Fling is godlike, it's extremely hard countered by spellshields, a problem which Ryze doesn't have. In addition, Fling is melee, on a champion with no gap closers, so it's pretty likely for Singed to just get knocked back before he gets to use it. Meanwhile Ryze's is an instant lock-on snare at range.

So tell me, why pick Singed over Ryze?