Real life does not have a tech tree.

• u/Iphikrates addresses how close the Greeks were (spoiler alert: that's not how any of this works);
• u/LuxArdens goes into why the Romans didn't mechanise;
• and u/dromio05 and u/wickie1221 also point out that the Medievals did have inventions of their own.

Moreover, you might want to see this excellent thread Someone on an Ask Reddit thread claimed research indicates that prior to Ptolemy VIII exiling academics from the Library of Alexandra, "they were only about ~300 years from full on industrialization." Is this true? If so, where can I learn more about it? written by u/Iphikrates and u/rememberthatyoudie

(I swear I spent 20 minutes looking for this specific thread, gave up, posted my other comment, then immediately found it >.<)

You might find these helpful

“The Roman Empire was closer to an industrial revolution than you think.” I’ve read/heard something like this numerous times. Is there any truth to it? written by u/LuxArdens and Did the Greeks ever use their steam engines for anything? written by u/half3clipse