To clarify, when a company is young, you have a lot of people wearing a lot of hats. They may in fact be quite good at wearing some of those hats. Likewise, having visibility and exposure to multiple domains aspects of the same company gives a perspective that is hard to have if you live in a super specialized silo.
However specialists don't need to be generalists to be productive as long as they come in with the mindset that they are specialists, and therefore may not know everything. And that is especially important, as I highlighted, for respecting historical context of the company and its operations.
There might be VERY good reasons for not doing something the way the rest of the industry does it (which is what the specialist might be inclined to do). However a good specialist should also be adept at factoring that into how they approach problems, and properly weigh the new information against their past experience to determine if in fact this is a special snowflake situation, or if their approach is still the right one. Conflict can often arise when if they push for the latter, so strong communication skills are key (and that is something that never really changes for any role at any stage of company growth).
I get where you are coming from. For me, being a long-term employee having gone through a few transitions from smallish to biggish, and when your storage guy you hired doesn't really know networking basics, or the database administrator has no clue about Linux, etc. it tends to slow everyone down.
"Scale" often seems to equate with SF hotshots from one of the big names that will come in and airdrop a brand new architecture. These things take years and you need those generalists that have the tribal knowledge and the ability to jump in (almost) as deeply as a specialized developer, DBA, Network Admin, etc. I think the SRE movement is good evidence of the type of breadth and depth needed to operate a complicated system at scale.
IMO that's a problem of hiring the wrong specialists, or BS artists in specialist hats (see the article's point about "the tech industry is not serious about hiring" :) ).
In other words, we have to go to war with the army we have, not the army we'd like to have. Sometimes waiting for just the right fit isn't an option, either because of the need to keep adding heads for growth, and sometimes you have situations like a Director (just brought in from BigDealCo to lead the growth) has a former employee that knows is "perfect" for the job. Director leaves after a year, after installing people that don't have skills. Catch-22 sometimes.
However specialists don't need to be generalists to be productive as long as they come in with the mindset that they are specialists, and therefore may not know everything. And that is especially important, as I highlighted, for respecting historical context of the company and its operations.
There might be VERY good reasons for not doing something the way the rest of the industry does it (which is what the specialist might be inclined to do). However a good specialist should also be adept at factoring that into how they approach problems, and properly weigh the new information against their past experience to determine if in fact this is a special snowflake situation, or if their approach is still the right one. Conflict can often arise when if they push for the latter, so strong communication skills are key (and that is something that never really changes for any role at any stage of company growth).