I remember 2015/2016 discourse in the alt right was almost all retarded

Indeed, it was. I started around late 2013 or possibly very early 2014 at the latest. In 2015-16 I used to frequent the TRS forum, and as you say, there were far more memes and trolling, and far more infighting and banning of people who were either degens or hostile trolls. It was more like 4chan pol (which I've never frequented) than anything else I can describe. Nowadays, however, I see less of those types around. I remember some loser calling himself 'Zon Kuthon' who particularly seemed to be mentally ill and who was finally banned after threatening to doxx someone if they didn't send him money. Next to outright infiltrators, it's these kinds of insane, criminally inclined shitheels that are most counter-productive to the cause.

Since Antifa degens have little access to functional people that would 'pass' as 'Far-Right' that mostly leaves the problem of the classic 'Feds', the state agents. Now, that isn't to say that there haven't been Far-Left non-state infiltrators in the past. I remember around 2015 that some idiot with a general skinhead appearance got into the NSM. Of course, the NSM had a lot of low-quality people, making it easier for Antifa to pass. He stole one of their flags and burnt it for his Facebook profile pic. But usually they're suspicious: one Antifa got into PF maybe a year ago, but people noticed that he was particularly out-of-shape and was probably also a homosexual. However, I think he was to do with the PF leaks because someone stupidly put him near their computer systems before he disappeared. We do need to get better at sniffing out infiltrators, particularly since they demotivate people from actually 'going irl', and the fear of them keeps people online.

I think the whole immature infighting/trolling/constant banning thing big in those times is still going on over at Telegram, but I've never used it to see for myself. I remember that Zoltanous character complaining about people spamming CP in his Telegram group. More recently, an older fellow by the name of TexasVet was lambasting one of the GDL people, who kept pushing the idea that he is a Fed. Whatever the case, I do think that a lot of the less serious and more subversive types have faded away over the years.

As for the 'Trump slump', I suppose I missed the obvious fact that PF and NJP did not predate the Trump era. I didn't really know anything about the TWP other than they existed, either. What I'm basing this on is the fact that so many people had confidence particularly in Trumpianism (e.g. that it would be the nucleus of a much larger 'Alt-Right' and that we were 'going mainstream'). This was, I remember thinking at the time, a total media fabrication. Basically, the mass media misappropriated the term 'Alt-Right' for a time and started using it all of a sudden to smear Trump, such that there was even a time when Trump claimed to be 'Alt-Right' until someone pointed out to him what it actually was and he naturally disavowed it. There was even a period for a few months where Trump supporters were calling themselves 'Alt-Right' and accusing us of bizarrely stealing 'their' label. But it ceased almost as rapidly as it started. I noticed years later that Greg Johnson seemed to think that was the apex of the movement: perhaps it was, but it was obvious that Trumpianism is very different from the 'Alt-Right', and if the Trumpianists kept using the label, it would have forced us to stop using it then and there. We couldn't possibly control the Trumpianists because they vastly outnumber us: there's millions of them. Rather than the 'Alt-Right' turning them into ethnonats, they'd end up controlling the 'Alt-Right' and turning it into civic nationalism instead.

Now, the reason why the mass media called Trump 'Alt-Right' was obviously to harm him by linking him to 'extremists', obviously with the intent of damaging his reputation among the masses. But those messages were interpreted differently by the real 'Alt-Right', since the identification of somebody with us naturally makes that person go up in our esteem: 'The mass media says he is like us, so he must be good'. Thus, for example, all the 'God Emperor' meme stuff of that time period. Furthermore, people who are viewed as bad by the mass media and the masses in general also seem to go up in our esteem, for example, all the anti-Putin and anti-Orban bullshit makes us like them a little bit more rather than less: there's the (usually correct) idea that if our enemies hate someone, they must be doing something right.

Of course, by 2019 at the latest even the most enthusiastic supporters of a 'Trumpianist-Alt-Right' fusion became very distanced from the Trumpians, and if anything we're at war with them these days.

But, on the topic of entryism, in 2016 just after Trump was elected, I remember a TRS guy who called himself 'Ghost' who did the stupid thing of showing his face on YouTube, and if I remember rightly, at the same time trying to get into the Republican Party. Unsurprisingly, he got himself doxxed and totally disappeared from the scene altogether. So there were at least some people (this guy and a few others at TRS) at the time who switched their opinion on the way forward to entryism, and that was the fault of Trump's rise and, in particular, of the mass media making him seem excessively 'bad' and 'fascistic' to the hoi polloi (which we naturally reinterpret as adding to, rather than subtracting from, a person's worth).