Yes, the Finnish study does not explicitly say that sexual abuse/trauma/an increasingly pornified society is directly linked to a trans identity particularly in teenage girls.
Two things to bear in mind, however.
The study comprises a retrospective chart review of all the SR applicants attending for assessment by one of the two adolescent gender identity services in Finland (Tampere University Hospital, Department of Adolescent Psychiatry) in 2011–2013.
The study was published in 2015. These kids were in the Finnish Gids - equivalent system from 2011-13. I would argue that porn and young people's access to it/smartphone use is far more ubiquitous now than back in 2015, let alone 2011. Pornhub, for example, only started in 2007.
The study does also find evidence of enormous amounts of bullying - we are not entirely sure how this was expressed and on what basis - but we know teenagers are frequently bullied for their sexuality, sexual orientation and gender expression as mentioned in the study. And what is bullying if not abuse?
It really is not a massive psychological leap or tin hattery to suggest that a girl may 'opt out' of womanhood for any number of reasons and decide on a male identity as a protective mechanism.
Another vote for the 'break it down for me' thread where there are loads of links to explore.