tbh my opinion isnt so much that trans men cannot have male privilege. its that the way we understand male privilege is based in cis women, specifically otherwise privileged (esp. otherwise-gendered privilege, i.e gender-conforming/straight/perisex) cis women's understanding of gender as something static and inherent to who you are, rather than something fluid which is, in part, constructed by society and placed onto you separately in every moment.
can a trans man experience (cis) male privilege? yes. can a trans woman? yes. and so can a cis woman! hell, a femme perisex cis woman with a gender neutral name could if she's assumed to be a cis man on a resume. male privilege is not an on/off switch. the idea that it is stems from cissexist understandings of male/female as entirely separate and static categories which everyone can and must be understood through. trans people in feminism are expected to constantly defend and deflect accusations of being Privileged Male Oppressors by promising cis perisex women that our experiences are just like theirs! we don't have any scary opinions that don't align with their worldview! we swear we won't ever make them have to reflect on how being cis+perisex has biased them and potentially made their analysis of gender at all inaccurate! trans experiences are only considered valuable to cisfeminism to the extent that they reaffirm what cisfeminists already hold true. thats why they only ever want to talk about a very simplistic narrative around wages pre/post-transition. its extremely unthreatening to cis people because it presents transness in patriarchy as just going from one cis role to another; it doesn't ask cis feminists to expand their paradigm to include the ways in which trans people are treated as a class and their own complicity in transphobic oppression.
which is why trans men have been getting fucked over by trans-affirmng cisfeminism. because by virtue of having our gender acknowledged, we are expected to forfeit our place in the feminist movement and adopt the role of outsider along cis men*. and its also why trans women and MTX people get fucked over the minute they cannot or refuse to describe their experiences through the one or two approved narratives. cisfeminism cannot tolerate transness-as-transness. it has to be compressed and reduced and diluted into something that fits within a cis-centric framework. we aren't allowed to have nuanced and intersectional conversations about trans men & other trans folks relationship with male privilege, the things we have to sacrifice to there, how fleeting it can be, the fact that for some of us being read as "biologically male" is actively more dangerous than being read as female... if it isn't familiar to cis women, then it means you aren't really oppressed.
*cis men should not be outsiders in feminism either btw but thats another post
