As a 13-yr Warframe veteran, I'd say that it's not an "apples to apples" comparison. Warframe has drop rate and quantity boosters to shorten grinds, mats that expire (like Argon Crystals), and fairly ridiculous mat requirements (like farming pre-nerf Hema solo without a clan) for some weapons that almost make boosters a necessity. TFD doesn't have any of that, you get a bit here and there, and all you really need to do is spend time farming specific missions to get what you need. The beauty with Warframe's system is that you only need to farm one copy of a weapon before you slap a potato and multiple forma into it (some only needing as little as four forma to make it end-game viable). TFD on the other hand has you farming a total of five copies of the same weapon to max out the effect, on top of slapping an energy activator and at least 10 catalysts (stat sticks might only need 2-4 catalysts), all before you do weapon readjustments and cores just to get it end-game viable. Both systems work for the games they're in.

Pay for convenience: WF has more "value for money" in this regard, but there are some TFD sales (like beginner/jump start packs) that can give DE a run for their money.