My understanding is that "radical" feminism means "to the root" which means addressing the root cause of oppression. (spoiler: it's men) I agree with the concept but don't know whether that makes me a radical feminist by other standards, because it seems so complicated now.

I also want to address the root cause of women's oppression, but it seems there is a specific philosophy detailed in literature by such people as Andrea Dworkin, Shelia Jeffreys, and Julie Bindel, which I do not agree with.

My understanding of political lesbianism as originally practiced had to do with devoting one's energy and time to women and withdrawing from the physical and emotional labor and did not mean compulsory genital activity with women.

I have heard that explanation before, but the fact is, prominent radfem activists like Julie Bindel (possibly a real lesbian, but it's hardly relevant because she believes that she chose to be a lesbian and that sexual orientation is a choice https://www.newstatesman.com/society/2014/07/julie-bindel-theres-no-gay-gene-and-i-love-idea-i-chose-be-lesbian) and Sheila Jeffreys do consider themselves actual, real, women-loving lesbians. From Sheila Jeffreys's book, "The Spinster and Her Enemies" :

Sheila Jeffreys is a lesbian and a revolutionary feminist who has been active in feminist campaigns against male violence, pornography and prostitution in Britain and in Australia for twenty years. She is a Senior Lecturer in the Department of Political Science at the University of Melbourne, where she teaches sexual politics and lesbian and gay politics.

She calls herself a lesbian and clearly thinks she's qualified to teach "lesbian and gay politics". I also saw a video of her where she said she was surprised and excited when she realized she could "choose to be a lesbian".

Your (and many others, I guess) concept of political lesbianism may be icky and too close to trans demands that we be attracted to them, but is not opposed to science or denies science in any way.

It is opposed to science because they're claiming that it's possible to choose your sexual orientation, which is simply impossible, and studies have shown that there are people who are truly only attracted to one sex. The fact that conversion therapy fails every time also gives credibility to the fact that sexual orientation is an immutable trait. As a lesbian, I'm sure you can understand that you will never be attracted to men, even if you really tried. Are you really saying that the claim that it's possible to choose your sexual orientation isn't anti-science?

what is anti-science

Other than the idea that you can choose your sexual orientation, I've also heard claims that PIV sex is completely unnatural. If a penis is never meant to enter the vagina, which they say should be used exclusively as a birth canal, then why does the cervix raise during ovulation? How are humans supposed to procreate? If the man were just supposed to put his penis right at the vaginal opening to ejaculate, then why wouldn't the cervix become lower in order to catch the sperm?

They also claim that birth is inherently an act that destroys women by design, which justifies their claim that all PIV is rape and women only enjoy sex with men because of trauma bonding. That does happen, but humans enjoy sex because it is necessary for the survival of the species, and the only reason birth is so traumatic and dangerous for humans is that farming caused us to have a diet that's poorer in nutrients, meaning a human won't grow as tall (therefore smaller pelvis), but the high carbs and sugar cause the baby to grow big. http://www.bbc.com/earth/story/20161221-the-real-reasons-why-childbirth-is-so-painful-and-dangerous