Tandy/RS were definitely one of the big early movers in the computer industry. And they didn't just repackage stuff; the TRS-80 line was their own thing. Only later did they start repackaging off the shelf stuff, though sometimes it had improvements over what was available elsewhere, like Tandy Graphics, which was basically the extra graphics modes from the IBM PCjr. but included in XT-class machines. That meant both businesses and home users could get EGA-like graphics for a fraction of the cost, without otherwise sacrificing computing power.
There are a few reasons why I think they don't have the same mindshare as other companies from the era:
1) They were more focused on businesses than home users or schools, so not as many people really grew up with them.
2) They didn't stay relevant very long. At one point they were the largest computer maker in the USA, with their own designs and software, but within only a few years they were an also-ran. By the mid to late-80's, they were basically just another IBM clone maker.
3) They're no longer in the business at all, so they're not making many new fans. Young people aren't buying new Tandys and then becoming interested in their history in the way they do with Apple or even IBM. Of course Atari, Commodore and others aren't in the business anymore either, but those brands had more home users as fans to begin with.
It's interesting for me to compare Tandy and Apple. Apple was very similar to Tandy in its early days, but they took divergent paths. If you flipped the script and said Tandy wouldn't make a PC clone but would just keep doing their own thing while Apple would instead commoditize their computers, it's very possible that we could now be saying "why doesn't anyone talk about Apple the way they talk about Tandy?" Tandy even had the built-in advantage of having its own network of stores, which they squandered over time.