This is changing - pap smears are being replaced by HPV tests, which only require a swab, no speculum exam. This catches cervical cancer just as well as smears do, while being far less invasive. Often this is being offered as a kit for the patient to do at home, or the provider offers to have the patient swab themselves in the office if they prefer it to the doctor doing the swab. Outside of smears, routine pelvic exams are no longer recommended in most countries. Speculum exams still happen if you have symptoms that need to be investigated, or if you test positive for HPV and need more detailed screening for cervical cancer, but they aren't the yearly occurrence for all women that they once were. A young woman growing up now might never experience a speculum exam at all if she never develops a health problem with the vagina or uterus/ovaries - just vaginal swabs every 3-5 years to check for HPV if she is sexually active. Clinical breast exams are likewise losing favour as a screening tool - now in most countries it is recommended only when the patient reports a lump or another symptom like nipple or skin changes. Using them as a screening test catches some cancers earlier, but because breast cancer treatment has improved so much, catching it earlier doesn't really change your outcome, while it DOES mean that a lot more women have anxiety due to false positives, or wind up treating a cancer that would never have progressed to a dangerous stage.
As with most changes in medicine, this happens in a piecemeal way. Many older doctors will continue as they always have until it's no longer covered by payors, and doctors who are transitioning from one technique to another may opt to do so with their younger patients first, rather than older patients who are used to the old standard and may feel anxious about "doing less" even if less is more, as in this case.
Plastic vs metal is more a matter of local trend - particularly, what was used in your medical training - and finances, weighing the cost of buying cases of new plastic specula vs the cost and hassle of maintaining an autoclave and having it inspected, etc. Specialist gynecologists are more likely to invest in metal, since they will need more variety of specula, not all of which are available in plastic, and once you have some metal, may as well do everything metal since you need an autoclave regardless. But a general family doctor, who is doing fewer and fewer speculum exams at all, would likely opt for plastic.