That's a very good point.
Besides, you know there's probably a social media intern at Marvel who is scouring the 'net for reaction anyway. The tweets will be seen even without @ someone or using a hashtag.
I don't think it was planned for another issue or that Marvel skipped an issue. I've seen speculation that the story we got was supposed to be issue #3 and they dropped the story for #2, because of the delay in publication. But if they were going to skip an issue, then they would've skipped the whole thing, including the cover.
I'm fairly certain the delay in publication was due to the
paper shortage and also the pandemic-induced limited capacity at printers. It's affecting all of publishing, not just comics. Marvel appears to be back on track, with all the remaining announced ASM issues having publication dates. For some reason ASM #5 isn't on Marvel's website, but it's scheduled for July 6 on retailer websites.
I'm placing my bet on #2 - the covers and solicits went done before Wells broke down his outline into scripts. And I honestly wouldn't blame Marvel for wanting a Peter/MJ cover early on. A) MJ covers sell; B) Putting out a cover several months in advance implying Peter & MJ break up at the start of Well's run helped to calibrate fan expectations.