@bendersteed It is definitely an issue, and the reason of much of the GS/Pleroma animosity towards Mastodon. Before 2016 that didn't happen, and the fediverse was around since at least 2008. Previous to that no one really minded what software you used, but Mastodon joined the fediverse with a very agressive marketing campaign and breaking protocols, so the fediverse ended up mostly splitting in two.
I think the real reason for this is that Mastodon was originally marketed for left wing people that wanted an alternative to twitter, while previous to that most of the fediverse was, while somewhat left-leaning, composed majorly of tech-oriented people with the exception of a few instances with a clear theme like rainbowdash.net
Thus, there was beyond the software issues that caused a period of constant server crashes and unintentional DDoSing of non-Mastodon servers that attempted to communicate with Mastodon (which had unilaterally modified the way the activitypub protocol was implemented from all previous software, thus causing overloads on servers that got weird data they couldn't parse, or simply way too much activity at once) a severe ideological and behavioural difference between the general public that used each software. People that have cultivated a mostly STEM campus-like community, with a huge overlap with the classical free software community and are generally open to debate on most topics, having "almost all conversations are open for everyone in any instance to join and give their opinion" as an unwritten rule of interaction really can't get along suddenly with a massive left-twitter migration from the late 2016 political climate. Originally a lot of people from the standing servers tried to interact with the new Mastodon communities like they had been with eachother for years just to be almost universally met with hostility or treated as extremely rude for interjecting into conversations, which in turn made them see Mastodon people as paranoid and prone to gang up on anyone who earned the dislike of one or two Mastodon users or said anything the newcomers didn't like (there's a bunch of screenshots floating around of Gargron himself joining in with a mob to harass @sim for wrongthink). Since many GS servers migrated to Pleroma or had their user set up Pleroma instances, as GS was poorly mantained by that point, the GS-Mastodon culture war ended up turning into Pleroma-Mastodon.

I think the core reason the fediverse reacted like it did is that Mastodon connected to an already established network and decided to do things as it pleased without any sort of consensus with the admins of existing instances on how to handle software issues, and when existing admins confronted Gargron on those software issues what they got was dismissal and insults from the new Mastodon community (which at that point was mostly just .social) and that in turn caused many of the existing communities to reply in kind.

Over time that got flanderized into "pleroma are nazis" and "mastodon are gay tankies" and a general two-way animosity.

And really, you can't blame a community that was mostly drama-free in the bigger picture for 8 years to be upset when someone strongarms their way in and forevermore turns that tranquility into a turf war, and never at an official level says "okay yeah maybe we went about things the wrong way, let's see about making up" nor the newcomers even try to adapt to the existing community, deciding to instead pretend anyone who complains is a nazi. No one likes when someone barges into their neighbourhood and tells them "the way you've acted all your life is wrong, change or we'll kick you out". I'm not going to pretend that there weren't jerks on this side startin fights and "counter trolling" after the "war" sparked, but the inital attempt was to interact and cooperate and it failed.