In addition to the other comments which more directly address your question, DNS has been / can be used to exfiltrate data from “secure” networks. Search “dns data exfiltration” in your favourite search engine and you’ll get several high quality articles. Typical mitigations might be to limit which DNS servers your network can contact, restrict packet sizes to the bare minimum which valid use would have and so forth.
This is appears to be dark pattern marketing at play; they run a Mastodon instance which intercepts all links to the federated content and pushes you towards their for-profit site; it was actually not doing this earlier, when I visited a few links I actually got real mastodon content pages inconsistently.
Generally, if you visit anything like https://flipboard.social/@[email protected] it redirects you to to flipboard.com/@AlaskaBeacon which is entirely their for-profit presence. But then it doesn’t a few tries later after testing more - I watched within a minute the Texas BBQ one allow me to see the profile on flipboard.social, I reloaded and was suddenly redirected to their flipboard.com/TexasBBQ site.
It seems you might be able to load them into your own mastodon instance manually and it will work (I do see a profile page with legacy posts which hadn’t federated yet, so “no posts” at this early of a test). Something like https://myserver.social/@[email protected] will presumably work; I suspect though that all posts will be stubs that drive you towards flipboard.com to read the actual content, rather than a direct source (time will tell).
edit: s/is/appears to be/ to give benefit of the doubt
Might I recommend https://liberapay.com/ ? As a user, I can donate with PayPal and they minimize vendor fees by collecting up front from me and performing recurring donations to you (lemm.ee) and it allows me to retain personal privacy if so desired (per the other reply). Here is the core Lemmy developer using the platform for example: https://liberapay.com/dessalines/ | https://liberapay.com/Lemmy/
On my Subscribed view on lemm.ee sorted by Hot which very recently upgraded lemmy-ui to 0.19.4 (your lemmy.sdf.org instance has not upgraded yet, just checked), of 14x news items/links which should have thumbnails - 8x of them are broken/missing, just over 50%.
It’s possible what you are seeing is more visible than before due to issue #2433 which is:
When images are broken, a blank space is all that is shown. A fallback image for broken images would make this more apparent.
With the 0.19.4 update I notice it a lot more now and see a lot from apnews.com causing this, on my Subscribed view with [email protected] and [email protected] (and others) this morning I count:
Sites that are fine: www.cnbc.com, www.nbcnews.com, www.bbc.com, www.cbsnews.com, newrepublic.com and a bunch of fediverse instances and other “not mainstream” sites from around the internet. it would appear that whatever has changed in code is interacting badly with certain mainstream news sites and the ability to get a thumbnail - I browsed the lemmy-ui commits and a metric ton of 3rd party dependencies were updated, gave up looking for the cause.
It is a disagreement between two entities (one large, one small) as to the use of EDNS, an extension to basic DNS, and is briefly outlined in Wikipedia. Using any other resolver, such as Quad9, instead of Cloudflare for your local DNS works as expected. https://en.wikipedia.org/wiki/EDNS_Client_Subnet#Controversy_over_lack_of_support
The one that’s stuck with me throughout a lifetime is The Hare and the Tortoise (Project Gutenberg, safe click). Slow but steady wins the race.