When one is wearing tefilin and takes them off to go to the bathroom the Mishna Berura and many others says that one should make another bracha on the tefilin after the bathroom. Does this din apply to both types of bathroom usage? Doesn’t the Derchai Moshe say that it is just a chumra to take off tefilin in certain cases in a bathroom, therefore maybe one shouldn’t say a bracha when putting them back on in certain cases. Also, if one were to take them off with daas to put them right back on and went in the bathroom to take a tissue would one put them on with a bracha in that case at all? Basically, what is the cause of the new bracha? The issur of wearing them at the time of the bathroom? Going into the bathroom? Also the Magen Avraham say that today since our bathrooms are closer than in the past one shouldn’t make a bracha. Why would the distance of the bathrooms matter?
Magen Avraham (25:22), as the question rightly notes, writes that today one does not make a new blessing after returning from a bathroom that is close by. This is also stated in Peri Megadim and in Derech Hachayim, and see also Os Chaim (25:16) who writes that this is the general custom. Kaf Hachaim (78) writes that one should make the blessing without Shem and Malchus.
However, the broad majority of poskim write that upon returning from a bathroom, even though it is not distant, one needs to make a new blessing. This is the ruling of Taz (11), Bach, and Biur Halachah in the name of Eliyah Rabbah, Chayei Adam (13:66), Rabbi Akiva Eiger, Orchos Chaim, Gra, and others, and this is the ruling of Radvaz (6:301), Shulchan Arcuh Harav (30), Maharsham (3:220, and Daas Torah), Ginas Veradim (see Be’er Heitev 53:3), Kitzur Shulchan Aruch (10:15), and this is the ruling given by Shevet Halevi and others.
However, for urination alone, Aruch Hashulchan (23, who also writes that one should make a new blessing) writes that one should not make a new blessing, and this is especially true for our bathrooms, which are clean and unlike bathrooms of old. See also Shevet Halevi (9:3).
For one who does not enter a full bathroom, but only a chamber where urinals are installed, one would certainly not make a new blessing, for it is permitted to enter such a chamber with one’s tefillin on.
Some write that those who usually make two blessings on tefillin should only make one blessing after leaving the bathroom.