Probiotics, not all are good quality.
I do agree to the opinion that all probiotics available in the market may not be of good quality. This can be addressed through multiple ways by checking the manufacturer details, branding, ingredient details, time since the product has been launched, performance reviews in the internet, claims on the product, licence authority etc. For sensory effects, it is advisable to purchase sachets of the products to feel the flavour & fragrance, color, aesthetics and palatability.
There are following ways that can be done -
1. Nonbusiness agencies/ regulators should issue a list of recommended probiotics and that should be displayed at each medical store. I don't know if its already there or not.
2. Technology can be a useful thing here. Thinking aloud but if each manufacturer places details/report from the third party of their product and that can be scanned through a simple QA code from their product box.
3. Online reviews, blogs are another source but these can mislead as well, so that should be handled with care.
I think there needs to be a restructuring of the way many of our natural products are labeled. There are high regulations on meat in the US, but little regulations on vitamins. I think many people have jumped on board that if it's labeled "probiotic" it must be good for you, like you mentioned. We need a grading system/regulations, something so that we know where are probiotics, vitamins, natural health care products are coming from and their quality.
Your question implies a scare based tactic on products and can be a valid tactic on informing others of poor quality but has significant risk depending on your role (industry, influencer, academic). No matter your opinion, leveraging a influencer could get the message out to a big population - bloggers such as Vani Hara "The Food Babe" has traditionally had significant influence in this space and she has many writings on probiotics (and quality) - https://foodbabe.com/search/probiotics
If your a manufacturer, emphasizing why your product is superior and high quality is the better route, not worrying about competitors on the market and the quality of their product.
If your a blogger, influencer, or consumer advocate - I would recommend getting a valid study funded (which with your background should not be a issue with a grant, crowd funding, etc) and then do a survey of various products to judge quality in a defendable method with the techniques like Sandeep mentioned combined with the microbiology on the probiotics.
Writing a review article on the health benefits and publishing your own paper on the quality might be a great publication!
A similar review of the benefits can be found here: https://www.researchgate.net/publication/258405079_Health_Benefits_of_Probiotics_A_Review