I think you may be overestimating how vital it is to have read all prior chapters to enjoy the latest chapter. Especially Detective Conan where most chapters are standalone crime procedurals and you’ll pick up a good amount of the premise through cultural osmosis.

But also, think about it: if you’re a Japanese kid who starts buying Shounen Sunday (though nowadays they would probably use the app), most of the series in there are going have been running for a while, no matter when you start. You’re not going to just ignore the bulk of the magazine that you bought with a significant portion of your pocket money just because you haven’t read the earlier chapters.