Would a new tag: [screen-time] be useful?
The new "screen-time" tag may help in tagging and searching for questions about any screen time related issues that are applicable to more than one device type: TV, computer, tablet, smartphone, etc.
The "screen-time" tag can replace and make more generic many single-device, more narrow tags, for example, "smartphone", but only if in fact the Q&A thread is more generic and applicable to, for example, "smartphone" and "tablet".
A brief search shows that "screen time" is a common topic on this stack (337 results as of this writing): https://parenting.stackexchange.com/search?q=screen
The term "screen time" is becoming more popular with time. For example, see PubMed search,
Results by yearplot in the upper right corner (2008: 22 articles, 2018: 307 articles): https://www.ncbi.nlm.nih.gov/pubmed/?term=%22screen+time%22
Yet, many threads either have one, narrow device tag (e.g., tagged with "computer", but actually applies to other screen types), or missing the device tag entirely:
tag "cellphone": Should we introduce screen time to our 27 month old?
tag "media" (expected: "television"?): How to make my 18-month-old son eat without screen time?
tag for device/screen missing: 10 year old's screen time: Studies and/or Government recommendations?
We have many tags already (but many tags have relatively fewer tags than the "screen" search results above).
One can search for "screen time", "screen", etc, without the "screen-time" tag (but tags do have many other uses, such as for watching, organizing, etc).