I don't think that is real - I don't believe every company was able to afford having DBA, Dev, QA, Business Analysts, Ops etc. as always fully separate FTE.
Only biggest companies were able to have that. If you have a single application to run there is no work for DBA as FTE, in big company where you have multiple projects you can most likely have DBA as a department that handles dozens of databases and running infra. Same with Ops, you can have SRE or OPS doing your infra if you have dozens of applications to run.
Problem is having separate QA/DBA/Dev/Ops departments was breaking because people would "do their stuff" and throw problems over the fence. So everything would go to shit and we have seen it in big companies.
Other thing is - I have read about multiple companies trying "to be professional" burning money on exactly having separate roles, but in reality you cannot simply afford FTE or having full department of DBA or QA or OPS or just Dev - unless you basically are swimming in money.
Only biggest companies were able to have that. If you have a single application to run there is no work for DBA as FTE, in big company where you have multiple projects you can most likely have DBA as a department that handles dozens of databases and running infra. Same with Ops, you can have SRE or OPS doing your infra if you have dozens of applications to run.
Problem is having separate QA/DBA/Dev/Ops departments was breaking because people would "do their stuff" and throw problems over the fence. So everything would go to shit and we have seen it in big companies.
Other thing is - I have read about multiple companies trying "to be professional" burning money on exactly having separate roles, but in reality you cannot simply afford FTE or having full department of DBA or QA or OPS or just Dev - unless you basically are swimming in money.