There was another question on META from a while ago that fondant asked about whether these questions are okay. Whoever answered the question hid their answer for some reason, even though they were totally right. But no, these questions aren't allowed on Pokebase.
This would be an example of a poll-type question:
No polls/opinion questions: Questions such as What is your favourite Pokemon? or Who is the best Water-type Pokemon are too open and vague to be useful. You can discuss things like that in Chat.
The very nature of the question is going to prompt multiple answers all imbuing people's opinions and past experiences with a certain Pokémon on their team. As the rules state, they're not needed and you'd probably get a shorter, more concise answer on the chat anyway.
Although I hate how short-reaching the captain worded this guideline, it's also a trivial question:
Avoid trivial questions: Anything that can be easily looked up on PokemonDb should not be asked. For example, questions like What level does Dewott evolve at? or What is Aqua Jet's base power? can be found in the pokedex and move pages respectively. (Note: if the answer could possibly be found on another site but is not here, then it is fine to ask it so that the answer is on this site.)
Comparing Pokemon really isn't that hard: open the Pokedex pages for the two Pokemon, look at their stats, how many weaknesses/resistances, and see what kind of moves they have.
Comparing Pokemon in a way that can benefit you can't really be answered by us because we have no context of what the rest of your team is as well, and as we all know, "I need a sixth member for my team" questions also aren't allowed on any of the Q&As.
Leave this kind of question for the chat: it's quick, easy, and you'll get an answer because members here are smartypants know-it-alls. >w>
A lot of these questions get approved. We used to be more lenient for these kinds of questions due to limitations in moderating and our previously small community, but with the influx of users and activity, more of an effort should be made to weed out these kinds of questions.