In accordance with the discipline a bhikkhu is prohibited from eating
fruit or vegetables containing fertile seeds. So when offering such
things, a lay person can either remove the seeds, or make the fruit
allowable by slightly damaging it with a knife. This is done by
piercing the fruit and saying at the same time "kappiya.m bhante"
(meaning "I make this allowable, sir.").
There is a rule for monks to not damage fertile seeds. This makes the monk both respect life and dependent on laypeople for their food. This also makes the layperson think about their actions.
I couldn't help but think that such rules actually harm the Sangha by preventing them from operating in present-day capitalistic societies
Present-day environmentally destructive capitalistic societies both tamper with nature's seed stock & diversity and even hold commercial control over seeds & also GMO seeds. The Vinaya rules offer an example of the importance of protecting seeds & seed stocks.
Other parts of the vinaya were surprisingly in-tune with modern sensibilities of social justice and "Twitter feminism", such as the rule forbidding monks from teaching nuns without being first asked.
Women are guests or visitors to the monastic community because, instead of starting their own monastic order, they asked to join the men. Refer to AN 8.51. The men did the hard yards of establishing Buddhism and gain gifts of property for monasteries then the women asked to join. While only senior monks can administer the nuns, it appears the nuns are expected to receive teachings of monks each fortnight. The scriptures say: "Each fortnight the nuns should expect two things from the community of monks: the date of the sabbath and visiting for advice."
It is also ironic radical feminist Western nuns claiming equality & independence also complain when they can't receive teachings from monks. In short, the Buddhist teachings were created by men. All Buddhist teachings are male teachings because the Buddha was a man. The scriptures (MN 115) clearly say an original Buddha cannot be a woman.
It is a right view in Buddhism to acknowledge there is mother & father in life. Any woman that cannot acknowledge & have gratitude towards good selfless deeds performed by men cannot be a Buddhist because they will have wrong view.
Is it permissible for a Buddhist lay follower, one who has taken
refuge and has chosen to follow the Eightfold Path
without picking and choosing, to discuss certain aspects of the vinaya in a skeptical light, as I have just done?
The Noble Eightfold Path includes "celibacy" in its 5th factor, called "abrahmacariyā". To quote:
And what is right action?
Katamo ca, bhikkhave, sammākammanto?
Avoiding killing living creatures, stealing, and sexual activity.
Yā kho, bhikkhave, pāṇātipātā veramaṇī, adinnādānā veramaṇī, abrahmacariyā veramaṇī—
This is called right action.
ayaṃ vuccati, bhikkhave, sammākammanto.
Therefore, only relatively few laypeople follow the Noble Eightfold Path. As for the Vinaya, it is not for laypeople. However, Buddhist laypeople should at least follow the Five Precepts but are not expected to follow the Noble Eigthfold Path.
The Vinaya is for monks & nuns. It is only necessary for a layperson to know Vinaya if they must regularly interact with a monk or a nun. This said, if this where the case, the monk or nun would instruct the layperson about the relevant Vinaya rules a monk or nun must uphold.
For example, if a layperson irregularly offers a monk or nun fruit with seeds, while I personally don't know the exact rules, I imagine the monk or nun will either refuse the offering or, otherwise, accept the fruit but not eat it (depending on the circumstances).
Or to describe certain texts as mythological or historical disciples
as impure?
The Vinaya is designed for purity. This topic has not yet identified anything "impure" about the Vinaya.
I have not taken refuge in the Three Jewels and will not unless I can
do so in total sincerity and a pure conscience.
Buddhism is not suitable for everyone. The Buddha said he only intended to teach those with little dust in the eyes. The Buddha often called his teaching 'Dhamma-Vinaya'. The Three Jewels include Vinaya, which promotes harmlessness & renunciation for monks & nuns and, most importantly, ensures appropriate protective boundaries between monastics & laypeople.
For example, contrary to Christianity, the Vinaya ensures there can be no protection of pedophiles and other sexual abusers within the Sangha. Unlike Christianity, which often believes in must exercise Christ's Forgiveness towards a sexually active priest, the Vinaya offers no such option. A monk or nun engaging in any external sexual act is immediately defeated &, when discovered, expelled from the Sangha.
potentially unsanitary?
The life of a monk is to dwell without fear. Monks don't check their alms food for poison, for example.