It's surely going to affect microsoft in the future.
Firstly, most devs are going to avoid kinect integration (as devs already do (TTF, Destiny)) in favour of the extra GPU power to bring their games visually closer to the PS4 version as possible.

Is this decision gonna hold back or limit gameplay on both consoles as a result, particularly xbox one.

Xbox One's minimum number of inputs for these games are
8 action buttons
1 system buttons
2 menu buttons
4-point D pad
2 Analog sticks

Xbox one without kinect has no voice commands now. So devs can't map additional features onto voice gestures for example varieties of taunts in-game.

PS4's minimum number of inputs are
8 action buttons
2 System buttons
1 menu button
4-Point d pad
2 analog sticks
Six axis motion sensor
*Touch pad w/ clickable button

*Touch pad has virtually unlimited actions, especially since it is multitouch.
Swipe up, down, left, right, corners
two fingers pinch
tap at specific points
tap & click
drag your finger
drag your finger & click

On top of a limited number of gestures with the sixaxis, but adding to the number of inputs.

Are xbox one games in the future going to be held back because of this. No motion control and no touch-based interface. Games like blacklight retribution use the touchpad for taunts. Since every button does something, I can't see how they'd be able to add taunts into a xbox one version. If they were to make the xbox one version, they'd either have to remove taunts, which means xbox one has a limited version of the game compared to its competitor. Similarly games like war thunder use the touchpad basically as a mouse trackpad, which isn't possible using xbox one's controller.

Or are companies going to do what they kinda do now, use the touchpad for maps panning and viewing of which you could otherwise do with the analog sticks?
Either way, with PC games making their way to consoles (and boy do they use a lot of buttons), either one console or another is going to get the short end of the stick because of xbox's limited inputs (if the game decides to remove kinect support in favour of 10% GPU powah)

tl;dr: READ IT ^^^

*also sorry nintendo you don't really count (yet) when it comes to third party making games, soon eh reggie?

The DS4 touchpad also has 4 different "regions" on it as well doesn't it? OH nvm, you did mention that.

Lol. Because every dev just jumps on the possibility to program for another set of superfluous controls.

Adding more possible actions is bad? Hmmok

Tilt 90° degrees to the left while moving your finger in circles over the touchpad while moving forward with the left analog and pushing L2 at the same time to drink potion.

Indeed virtually unlimited :p I really think that the touchpad is a great improvement. Works perfect in Killzone in my opinion and there are more games that use it in a nice way.

I thought that said 'religion' for a moment. :O

Yea cause the touchpad and six axis enhance the game experience by so much right? Lolll

i love the touchpad, its use as a mouse has to be one of my favorite.

But thats the thing, you dont have to dev for every single possible combination of inputs, but it's nice to have a virtually unlimited pool of inputs for you to dev for if you need.

Buttons will always be prioritised but the touchpad now means devs can add more features into their game(say from a pc version) without shoving everything into the pause menu or having some weird button combination e.g hold r1,r2,l1 and x to perform taunt

also, last gen it was impossible because of not enough button combinations, but imagine skyrim/ES with a swipe up to quick save feature. Now how would they add that onto xbox one if they decided not to use kinect for parity reasons.

Did I say it was bad?

I only said that any dev with half a brain will ignore the additional functions of the touchpad. Like every dev is ignoring SIXAXIS or Kinect functions.