First of all: the p2p address lookup is an optional feature. You have to explicitly enable it.

Mainline is incredibly frugal in terms of resource use, but we want it disabled by default so mobile apps don't look like bittorrent clients and get flagged by the OS.

When we do a p2p address lookup, every mainline server node could possibly be responding. Any bep_0044 record gets stored on 20 random mainline server nodes.

So a bittorrent client that participates in the DHT as a server and is long running enough to be included into the DHT routing tables will respond, yes.