How tuff is it to fish out of kayaks for smallmouth?

What would be tough about it?

I see people pulling in huge saltwater fish from a kayak/canoe so a simple small mouth should be no problem, just reel in like normal and if it pulls the boat, no worries you can move back if you liked that spot

An Eskimo can harpoon & fight a 300 lb seal from one. Me thinks a 3 lb smallie would be slightly less difficult.

I've caught reds, snook & small tarpon from them. Your two disadvantages are that you're not elevated enough to see anything under the water, and it can be hard to get leverage for a good hook set. ( not a concern with the fish you are talking about).

Keep a small river anchor on the deck behind you, when you hook one, reach behind you & knock the anchor overboard while holding the rod with one hand. Not the most graceful of moves, but it keeps you in one spot.

94% of the time I fish from a yak.

Get a boat you can stand and fish from....