This script checks if a page is bfcache eligible and prints reasons if it isn't. It can be easily modified to check multiple pages.

bfcachetest.js

// This script checks if a page is bfcache eligible and prints reasons if it isn't.
// It can be easily modified to check multiple pages.

// Chrome crbug: https://bugs.chromium.org/p/chromium/issues/detail?id=1312486
// Puppeteer issue: https://github.com/puppeteer/puppeteer/issues/8182

const puppeteer = require('puppeteer');

(async () => {    
    // Configuring and launching the browser
    const browser = await puppeteer.launch({
        headless: false,
        args: [
            '--window-size=1920,1080',
            '--enable-features=BackForwardCache'        // Enabling BackForwardCache, some versions of Puppeteer have this disabled by default (https://github.com/puppeteer/puppeteer/pull/8196)
        ]
    });
    try {
        const page = await browser.newPage();
        await page.setViewport({
            width: 1920,
            height: 1080
        });
        // Creating a CDP Session to listen for CDP Page events
        const session = await page.target().createCDPSession();
        await session.send('Page.enable');

        // Defining the URL you want to test and creating the output object
        const url = new URL('https://developer.google.com/');
        const output = {
            'url': url,
            'notRestoredReason': []
        };
        // Listening for a CDP Page.backForwardCacheNotUsed event and adding the notRestoredExplanations to the output object if present
        session.on('Page.backForwardCacheNotUsed', async (bfcache) => {
            if (bfcache.notRestoredExplanations){
                output.notRestoredReason = bfcache.notRestoredExplanations;
            }   
        });
        // Navigating to the URL. Update the waitUntil and timeout options according to your website rendering behaviour
        const navigationOptions = 
        await page.goto(url, {
            waitUntil: 'networkidle2',      // Navigation is considered to be completed when there are no more than 2 network connections for at least 500 ms
            timeout: 0                      // No timeout
        });
        // Navigating to chrome://terms copying what the DevTools bfcache test does
        await page.goto('chrome://terms');
        // Navigating back to the URL. Using a workaround as Puppeteer it seems to have a bug when a page is restored correctly from the bfcache
        try {
            await page.goBack({
                waitUntil: 'networkidle2',      // Navigation is considered to be completed when there are no more than 2 network connections for at least 500 ms
                timeout: 240                    // Setting a very long timeout because when bfcache is used a TimeoutError is fired instantaneously (Puppeteer issue?). The waitUntil event will be fired before the timeout.
            });
        } catch (error){
            // We are expecting a TimeoutError if the page is using bfcache correctly
            if (error.name != 'TimeoutError'){
                console.log(error);
            }
        }
        // Closing the page
        await page.close();
        // Closing the browser
        await browser.close();
        // Printing the result
        console.log(JSON.stringify(output, null, 4));
    } catch (error) {
        // Printing errors
        console.log(error);
    } finally {
        // Closing the browser if an error occurs, no mercy for zombies
        await browser.close();
    }
})()