It is not that they forgot how to make good batteries. The car designers keep wanting the same CCA but in a smaller lighter package. To get that requires compromises. in this case they have to make the plates thinner and out of a foam like lead to get the same surface area as the old ones had with thicker and more plates. Thinner plates will not last as strong and will fail sooner. All that the car designers care about is a smaller lighter battery that will get past the 36 month new car warranty. I just had to replace a 3 year old battery in my truck, it is a 2011 and this is its 3rd battery. But the battery is smaller and lighter with more CCA than the monster that was in my old truck and lasted 6-7 years.
Everything in electronics is a compromise you want more CCA you have to give something else up, size, or weight, or longevity. Nowadays they are giving up longevity in exchange for CCA and size.
For the bike I still like the good old flooded cell Yuasa. it has less CCA than an AGM, but those big thick plates last a long time. The bike was designed to work with the lower CCA of the Yuasa.