I am still facing the same issue!

I have been having similar issues selecting with a mouse on a 5K monitor for the last several versions of Illustrator. I have to zoom way in to precisely select items. Can imagine the difficulties that drastically differing monitor resolution plays into the programming of these applications and look forward to a day when selecting isn't as cumbersome..

Someone mentioned that when smart guides were on that's when they had the problem.

I turned ON smart guides and that fixed it! Now when I get close to a line or other vector object, it gets highlighted and I can easily move it even when zoomed out a lot.

Thank you for solving a whole lot of frustration.

Finding it nerve wracking to constantly be clicking and clicking, trying to select lines and areas.

I only noticed this bug when 'Smart Guides' was turned on.
I usually don't use smart guides as AI's snap is so inaccurate I've learned not to assume just because the app is indicating that a snap is made (after trying multiple snap/selection tolerance settings), on closer inspection, so called snapped points are miles off. The only way is to work at maximum zoom.

Illustrator 8 was the last version that had accurate snap: over 20 years ago. Probably the one of the basic time saving functions a vector app needs to get right (along with accurate selection tools).

It's like bring out a new car with all new bells and whistles every year, but without fixing a steering problem that keeps taking you in the wrong direction. I just don't understand Adobe's thinking, or lack of it.

Back to the point: Switch off Smart Guides and the selection of lines is then no longer locked.
And don't use NotsoSmart Guides.

Still isn't fixed - this is so annoying. We want old illustrator back - new versions suck

Almost December 2020... and it is still an issue. So frustrating.

I just updated to the latest verstion (25) and this is STILL an issue... I click on a stroked line and unless I click EXACTLY on the tiny tiny center line of the stroke, I can't click it. This is nearly impossible!

I'm still having this issue in 24.3

This issue is still not resolved. Even zoomed in to the max I am unable to select a path. This is creating a huge problem using this software. Those of us who use paths heavily are completely shut down by this bug. Adjustment to the 20px tolerance makes no difference. Please advise when this might be addressed.

STILL NOT FIXED - INFURIATING!! I have to lock everything else so I can drag my selection tool over the line.

You guys still haven't fixed this issue????!!!

I was having issues too and had to look it up just to see if I'm going crazy over here as I've been using Illustrator for over 20yrs now. SMH, come guys, let's get this corrected!

Still. Not. Fixed.

Thanks for the link Ankit. I've tested on both Mac (Mojave) and PC (Windows 10 latest build) and it's still not working as intended unfortunately.

The selection arrow cursor will change to the cursor with dot to indicate that it is within selection range and one of two things will happen: if Smart Guides are OFF the cursor will just draw a box selection marquee instead; if Smart Guides are ON the cursor will grab the path/object as intended. This is the same across both Mac and PC. WIth Smart Guides off you still need to be basically on the 1px of the path to select it.

Using Smart Guides with everything turned OFF except for Object Highlighting is a current work around to this problem, but is not ideal as if you want to use the handy alignment functionality (which is too intrusive for general illustration work) then you have to keep digging back into the preferences to turn it on and off again. This is a separate suggestion really, but with that in mind, I'd love if the Smart Guides preference was in a dockable palette so we could just toggle the functionality of them as needed. Even with these issues aside, it seems kind of odd to have them buring in preferences?

Here is a video of me trying to select a line using 24.1.2 with a selection tolerance of 20.

https://www.dropbox.com/s/qys37dexia7exhn/IMG_7562.mp4?dl=0

I installed 24.1.2 beta. I set the tolerance to 20. I'm still having this problem. I have to select exactly the line exactly 1 or 2 pixels in order to select and drag it. So, it's not fixed.

Using 24.1. and it is still very hard to select a line using a Retina display and Wacom. There is no pixel tolerance at all. You need to select exactly 1 pixel to the line to select or drag it. This is especially hard to do on lines larger than 1 point.

When creating a symbol, it has to be static otherwise it won't move with the selection tool.
Hope this helps.

Ankit: I sent you a video and info of my settings, version and OS. I encourage others to do also because I think it's a broader issue that is NOT affected by preference settings.